Patent ID: 11556070

Abstract:
According to the present invention, there is provided a carrier core material that is formed of ferrite particles in which 48 to 52 mass % of Fe, 16 to 22 mass % of Mn, 1.0 to 3.5 mass % of Mg and 0.05 to 0.5 mass % of Ca are included, and when an electrical resistance value with an applied voltage of 500 V in an environment (in an L/L environment) in which the temperature is 10° C. and the relative humidity is 35% is RL (Ω·cm), and an electrical resistance value with an applied voltage of 500 V in an environment (in an H/H environment) in which the temperature is 30° C. and the relative humidity is 70% is RH (Ω·cm), formula (1) below is satisfied. 0.1≤(log RL−log RH)≤0.3  (1)