High density information records made of conductive resin compositions comprising inorganic power stabilizers
AssigneeVictor Company of Japan, Ltd.
InventorsKazuhira Namikawa, Toshiaki Hamaguchi, Mutsuaki Nakamura, Akio Kuroda
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Abstract
High density information records made of vinyl chloride resin compositions which comprise conductive powder and inorganic compounds in the form of powder having an antacidic action and a predetermined average size. By this, dropout defects in the information record can be suppressed to a significant extent. The inorganic compounds are selected from calcium hydroxide, basic aluminum magnesium carbonate hydrate and hydrotalcite.
Claims6
A high density information record of an electrostatic capacitance type which comprises a record substrate on which signal information is recorded as geometric variations, the substrate being made of a conductive resin composition comprising a vinyl chloride resin, 5 to 30 parts by weight of a conductive powder and not greater than 10 parts by weight of an inorganic stabilizer capable of suppressing a dehydrochlorination reaction occurring in the vinyl chloride resin during a processing operation and capable of fixing hydrochloric acid produced during the operation, said inorganic stabilizer being selected from the group consisting of calcium hydroxide, basic aluminum magnesium carbonate hydrate and hydrotalcite and being in the form of a powder having an average size below 10 .mu.m and an antacidic action, both based on 100 parts by weight of the vinyl chloride resin, whereby dropout defects of the record are greatly reduced.
Dependencies are inferred from the claim text.