| 摘要 |
PROBLEM TO BE SOLVED: To obtain a recording material utilizing the change in physical properties, which is expressed by the formula La1-x-yEuySrxMnO3 wherein (x) and (y+x) are specified. SOLUTION: An Mn perovskite-type oxide is expressed by the formula La1-x-yEuySrxMnO3, wherein (x) is <0.15 and (y+x) is >0.15. When (x) is <0.08, the magnetism of the oxide is transferred from antiferromagnetism to ferromagnetism and the electroconductive property of the oxide is transferred from insulative property to metallic property, thereby the electroconductivity is improved, when the oxide is optically exited. Further, when (x) is >0.08 and <0.15, the electroconductive property of the oxide is transferred from insulative property to metallic property and the electroconductivity is improved, when the oxide is optically-exited. The Mn pervoskite- type oxide is obtained by weighing raw materials of La2O3, Eu2O3, SrCO3 and MnO so that a prescribed composition is obtained after firing, then mixing and pulverizing the raw materials using a wet-type ball mill to obtain a slurry, drying the slurry, then once calcining the dried material at 1,000 deg.C in air for several hours, again mixing and pulverizing the calcined powder using the wet-type ball mill, further drying the obtained slurry, forming the dried powder using a metal mold and firing the formed body at 1,200 deg.C in a flow of gaseous oxygen for 10 to 20 h. |
