Magnetic tape

Abstract

A magnetic tape including: a nonmagnetic support; a substantially nonmagnetic layer containing nonmagnetic powder and a binder; and a magnetic layer containing ferromagnetic powder and a binder, in this order, wherein the magnetic tape has a coefficient of temperature expansion of from 0 to 10×10−6/° C. and a coefficient of humidity expansion of 0 to 7×10−6/% RH each in a transverse direction of the magnetic tape, and the magnetic tape has a dimensional deformation amount of from 0.01 to 0.06% in the transverse direction in case of applying a tensile stress of 1N to the magnetic tape at 60° C. for 50 hours in a longitudinal direction of the magnetic tape.

Description

Claims

1. A magnetic tape comprising: a nonmagnetic support;a substantially nonmagnetic layer containing nonmagnetic powder and a binder; anda magnetic layer containing ferromagnetic powder and a binder, in this order,wherein the magnetic tape has a coefficient of temperature expansion of from 0 to 10×10−6/° C. and a coefficient of humidity expansion of 0 to 7×10−6/% RH each in a transverse direction of the magnetic tape, and the magnetic tape has a dimensional deformation amount of from 0.01 to 0.06% in the transverse direction in case of applying a tensile stress of 1N to the magnetic tape at 60° C. for 50 hours in a longitudinal direction of the magnetic tape.

2. The magnetic tape according to claim 1, which has a Young's modulus of 6 GPa or higher in the longitudinal direction of the magnetic tape.

3. The magnetic tape according to claim 1, wherein the nonmagnetic support has a Young's modulus of 6.0 GPa or more in a longitudinal direction of the nonmagnetic support.

4. The magnetic tape according to claim 1, wherein the nonmagnetic support has a Young's modulus of 7.0 GPa or more in a longitudinal direction of the nonmagnetic support.

5. The magnetic tape according to claim 1, wherein the nonmagnetic support has a Young's modulus of 8.0 GPa or more in a transverse direction of the nonmagnetic support.

6. The magnetic tape according to claim 3, wherein the nonmagnetic support has a Young's modulus of 8.0 GPa or more in a transverse direction of the nonmagnetic support.

7. The magnetic tape according to claim 4, wherein the nonmagnetic support has a Young's modulus of 8.0 GPa or more in a transverse direction of the nonmagnetic support.

8. The magnetic tape according to claim 1, wherein the nonmagnetic support has a Young's modulus of 9.0 GPa or more in a transverse direction of the nonmagnetic support.

9. The magnetic tape according to claim 3, wherein the nonmagnetic support has a Young's modulus of 9.0 GPa or more in a transverse direction of the nonmagnetic support.

10. The magnetic tape according to claim 1, wherein the nonmagnetic support has a Young's modulus of 11.0 GPa or more in a transverse direction of the nonmagnetic support.

11. The magnetic tape according to claim 3, wherein the nonmagnetic support has a Young's modulus of 11.0 GPa or more in a transverse direction of the nonmagnetic support.

12. The magnetic tape according to claim 1, wherein the magnetic layer has a dry thickness of from 10 to 100 nm and a coercive force of 159.2 kA/m or higher.

13. The magnetic tape according to claim 1, further comprising: a reinforcing layer containing a metallic material selected from metals, semimetals, alloys, and their oxides and composites, provided on at least one side of the nonmagnetic support.

14. The magnetic tape according to claim 13, wherein the reinforcing layer is provided on both sides of the nonmagnetic support.

15. The magnetic tape according to claim 13, wherein the reinforcing layer has a thickness of from 20 to 500 nm.

16. The magnetic tape according to claim 13, wherein the reinforcing layer has a thickness of from 20 to 300 nm.

17. The magnetic tape according to claim 13, wherein the reinforcing layer contains at least one of Al, Cu, Zn, Sn, Ni, Ag, Co, Fe, Mn, Si, Ge, As, Sc and Sb.