Rare earth oxysulfide-based cold storage material

Abstract

Provided is a cold storage material having a large thermal capacity in a ultra-low temperature range of 10 K or less and being highly durable against thermal shock and mechanical vibration. The cold storage material contains a rare earth oxysulfide ceramic represented by the general formula R2O2S (wherein R is one or more kinds of rare earth elements selected from La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y), and Al2O3 having a specific surface area of 0.3 m2/g to 11 m2/g is added to the cold storage material.

1 . A rare earth oxysulfide-based cold storage material comprising a rare earth oxysulfide ceramic represented by the general formula: R2O2S, wherein R is one or more rare earth elements selected from the group consisting of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y, and, wherein the rare earth oxysulfide-based cold storage material further comprises Al2O3 added thereto in an amount of 3 to 12% by weight in terms of aluminum. 
     
     
         2 - 3 . (canceled) 
     
     
         4 . The rare earth oxysulfide-based cold storage material of  claim 1 , wherein the Al 2 O 3  has a specific surface area of 0.3 m 2 /g to 11 m 2 /g. 
     
     
         5 . A regenerator filled with the rare earth oxysulfide-based cold storage material of  claim 1 . 
     
     
         6 . A regenerator filled with the rare earth oxysulfide-based cold storage material of  claim 4 .