Patent ID: 11898116
Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
Field: Basic materials chemistry (Chemistry)
Classification: CPC G  C | IPC C  G

Claim 18:
19. A method to determine a dewetting thickness of a lubricant, comprising:
(a) generating a chemical representation of the lubricant including a plurality of segments, each linked together through an ether linkage according to a general formula:

Re1-Rb1-Ri-Rc-Ri-Rb2-Re2;

wherein Rc is a divalent center segment including a perfluoroalkyl ether moiety;
wherein each of Rb1 and Rb2 is, independently, a sidechain segment including a perfluoroalkyl ether moiety;
wherein each Ri is, independently, a divalent linking segment including a functional group including elements from Group 13-17 of the periodic table of the elements;
wherein each of Re1 and Re2 is, independently, a monovalent end segment including a functional group including elements from Group 13-17 of the periodic table of the elements; and
wherein Rb1≠Rc≠Rb2;
wherein the lubricant has a bonding percentage of about 70% to about 100% corresponding to a total area of a surface on which the lubricant is located;
(b) determining a segment weight average molecular weight (α) according to the formula:

α=[molecular weight of Rb1+molecular weight of Rb2+molecular weight of Rc]÷3; and

(c) determining the dewetting thickness, Tdw, of the lubricant according to the formula:

Tdw=0.0045(α)+8.0226.