PURPOSE: To prevent generation of microvoids by forming an insulated block with a cross-linked polyethylene composition obtained by mixing, as the essential elements, the chemical cross-link agent and at least a kind of age resistors selected from a particular group into polyethylene.
CONSTITUTION: An insulated block is formed of a cross-linked polyethylene composition in which a chemical cross-link agent and at least a kind of age resistor are mixed, as the essential elements, to plyethylene to control decomposition of walnut alcohol. The age resistor is selected from dilaurylthiodipropionate, ditridecylthiopropionate, distearylthiodipropionate, tetrakis[ethylene-3-(n- dodecylthio)propionate] methane, bis[2-methyl-4-{3-n-alkyl(C12 or C14) propionyloxy}-5-t- -buthylphenyl] sulfide, tris(2,4-di-t-buthylphenyl) phosfite, tris(nonylphenyl) phosfite, etc.
SHIMADA MICHIHIRO
NODA HAJIME
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