Magnetic tape and magnetic tape cartridge

Abstract

A magnetic tape comprising a non-magnetic support, a magnetic layer containing magnetic powder which is formed on one side of the non-magnetic support, a primer layer containing non-magnetic powder which is formed between the non-magnetic support and the magnetic layer, and a backcoat layer containing non-magnetic powder which is formed on the other side of the non-magnetic support, wherein the magnetic layer contains the magnetic powder which comprises plate, granular or ellipsoidal magnetic particles with a particle diameter of 5 to 50 nm, and has a thickness of 0.09 μm or less, and wherein at least one of the primer layer and the backcoat layer contains non-magnetic plate particles with a particle diameter of 10 to 100 nm.

1 . A magnetic tape comprising a non-magnetic support, a magnetic layer containing magnetic powder which is formed on one side of the non-magnetic support, a primer layer containing non-magnetic powder which is formed between the non-magnetic support and the magnetic layer, and a backcoat layer containing non-magnetic powder which is formed on the other side of the non-magnetic support, wherein the thickness of the magnetic layer is from 0.05 μm to 0.09 μm, and wherein the rate of fluctuation in reproducing output in at least one of the tape lengthwise direction and the tape widthwise direction is 8% or less when signals with a wavelength of 2 μm are recorded on said magnetic tape with a magnetic induction type recording head having a recording track width of 76 μm and are reproduced with a magnetoresistance type reproducing head a having track a width of 38 μm (the thickness of a magnetoresistance type element: 0.05 μm).  
     
     
         2 . The magnetic tape according to  claim 1 , wherein said magnetic layer contains the magnetic powder which comprises plate, granular or ellipsoidal magnetic particles with a number-average particle diameter of 5 to 50 nm, and wherein at least one of the primer layer and the backcoat layer contains non-magnetic plate particles with a particle diameter of 10 to 100 nm.