Patent ID: 6555197
Filing Date: 2003-04-29
Classification: G11B,Y10T

Abstract:
A lubricant for a magnetic disk to be coated thereon, comprising a perfluoropolyether having a following formula (1),R1â€”CF2O&Brketopenst;&Parenopenst;CF2CF2O&Parenclosest;m&Parenopenst;CF2O&Parenclosest;n&Brketclosest;CF2â€”R2â€ƒâ€ƒ(1), where R1 and R2 are each a univalent organic group, and m and n are each a positive integer, whereina component of said perfluoropolyether having number average molecular weights less than 1000 is smaller than 10 wt. %, and a component thereof having number average molecular weights not less than 7000 is smaller than 15 wt. %; a ratio between a weight average molecular weight and a number average molecular weight is smaller than 1.5; and a substitution ratio of a terminal functional group that secures an adsorption force of the lubricant is not less than 90%.