A new γ-Fe2O3particle exhibiting improved orientation

A new γ-Fe
2
O
3
particle (RX-2228) exhibiting squareness ratios as high as 0.90 was compared with other γ-Fe
2
O
3
particles in the same tape formulation. The particle volume concentration was 11% larger and the Br 25% larger for RX-2228. The anhysteretic susceptibilities for an unoriented and oriented RX-2228 tape (having the same Br) were 2.12 and 2.72, respectively. Surprisingly, the long wavelength sensitivity was the same for the two tapes. The recording advantages of RX-2228 arise from a greater tape Br and a switching field distribution which is half that of commercial tapes. Compared with a professional mastering tape, RX-2228 was better by 3.1 dB in S/N ratio, 3.3 dB in saturated output at 500 Hz, and 4.3 dB in saturated output at 15 kHz at 7-1/2 in/s.