Magnetic recording tape with double layer coatings

The use of the compact cassette system has become very popular in recent years. The system operates on a tape speed as low as 4.75 cm/s but the user is demanding that its signal quality approach more closely the quality of the conventional reel-to-reel system that operates at a much higher tape speed. To meet this requirement, much work has been done on the development of the amplifier, the transducer head, the tape transport system, and the magnetic tape itself. In our case, we have developed a tape of novel structure principally to achieve this goal, and we are happy to report very satisfactory results. The tape has double magnetic coatings and consists of the tape base, an under layer of γ-Fe
2
O
3
, and an outer layer of CrO
2
. The new tape has an extended frequency range, excellent linearity and high maximum output level throughout the frequency range, excellent
S/N
ratio, wide dynamic range, and is useable with a bias current compatible with the conventional γ-Fe
2
O
3
tape.