COATING MATERIAL FOR PARTIAL-DISCHARGE RESISTANCE, INSULATING COATING FILM FOR PARTIAL-DISCHARGE RESISTANCE, ELECTRICAL WIRE, AND DYNAMO-ELECTRIC MACHINE

摘要

Provided is a coating material for partial-discharge resistance which has excellent alumina-particle dispersibility and a viscosity suitable for industrial use and which is capable of forming coating films excellent in terms of partial-discharge resistance and insulating property.The coating material for partial-discharge resistance comprises: at least one heat-resistant resin selected from the group consisting of polyamide resins, polyimide resins, polyimide resin precursors, polyamide-imide resins, polyetherimide resins, and polyesterimide resins; alumina particles represented by the formula Al₂O₃·nH₂O and having an aspect ratio of 2-99; at least one compound selected from the group consisting of organophosphorus compounds, sulfonic acid compounds, amic acid compounds, triazole compounds, compounds represented by formula (A), compounds represented by formula (B), compounds represented by formula (C), citric acid, ethylenediaminetetraacetic acid, and ethylenediaminetetraacetic acid derivatives; and a solvent. The solvent comprises 90 mass% or more solvent having a boiling point at 1 atm of 100°C or higher. The alumina particles are contained in an amount of 10-30 mass% per 100 mass% the sum of the heat-resistant resin(s) and the alumina particles. The total content of the heat-resistant resin(s) and the alumina particles is 10-30 mass%.