Biaxially oriented, unidirectionally long polyethylene-2,6-naphthalate film and magnetic tape therefrom
US5415930A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 14, 1994 |
| Grant date | May 16, 1995 |
| Priority date | — |
| Expiry date | Jan 14, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31786
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A biaxially oriented, unidirectionally long polyethylene-2,6-naphthalate film, (A) which contains PA1 (a) 0.05 to 0.4% by weight of first inert solid particles having an average particle diameter of 0.05 to 0.3 .mu.m, and PA1 (b) 0.005 to 0.05% by weight of second inert solid particles having an average particle diameter of 0.3 to 1.0 .mu.m, this average particle diameter being greater than the average particle diameter of the first inert solid particles by at least 0.2 .mu.m, wherein: (B) the Young's modulus in the length direction is at least 650 kg/mm.sup.2, the Young's modulus in the width direction is at least 600 kg/mm.sup.2, the Young's modulus in the length direction is greater than the Young's modulus in the width direction, (C) the heat shrinkage factor in the length direction in heat treatment at 70.degree. C. for 1 hour under no load is not more than 0.08%, and (D) the surface roughness, Ra, is 3 to 10 nm; and a magnetic tape obtained therefrom.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.