Hgst Netherlands, B.v.

Hitachi Global Storage Technologies Netherlands B.v.

International Business Machines Corporation

Robert Waltman

Xing-Cai Guo

Bruno Jean Marchon

John Martin Burns

Hong Deng

Daryl J Pocker

Malika Dothresa Carter

Run-Han Wang

Norbert A Feliss

Tsai-Wei Wu

Thomas A Gregory

Vedantham Raman

Timothy Martin Reith

Paul Marion Green

Bala Krishna Pathem

Yoshihiko Ooeda

Mina Amo

Owen R Melroy

Garth Wade Helf

Eric Christian O'Brien

Jinliu Wang

Alan P Giorgi

Yuichi Aoki

Qin Pan

Anthony L Smith

Yu-Chen Wu

Yuzuru Shimazaki

According to one embodiment, a lubricant includes a multidentate perfluoropolyether having a chemical structure of: R&#x2014;R&#x2014;R&#x2014;R&#x2014;R&#x2014;R&#x2014;R, where Rincludes at least one perfluoroethyl ether unit, and where Rand Reach include at least one functional group configured to attach to a surface. According to another embodiment, the aforementioned lubricant may be suitable for use in a sub-nanometer thick lubricant layer for various applications, and particularly useful for magnetic recording media.

Ultra-low profile multidentate lubricant for use as a sub-nanometer thick lubricant layer for magnetic media

A method, system and apparatus are disclosed for forming a lubricant film for magnetic recording applications. The method includes, in certain embodiments, providing at least one substantially solvent free lubricant having a plurality of lubricant molecules with each lubricant molecule comprising a polymer chain having a backbone section and at least one functional end group. The method also includes treating the at least one substantially solvent free lubricant with a physical treatment to cross-link the backbone section of each polymer chain with at least one other molecule to create a cross-linked lubricant.

UV cross-linking neat lubricant mixtures for magnetic recording media

A surface agent includes two end portions and a middle portion disposed between the end portions. The end portions include a terminal section and a midsection. The terminal section includes at least one surface active functional group. The midsection includes at least one perfluoroethyl ether unit. The middle portion includes at least one perfluorobutyl ether unit.

Perfluoropolyether lubricant and systems comprising same

A surface agent includes two end portions and a middle portion disposed between the end portions. The end portions include an anchor group or a truncation group. The anchor group includes at least one surface active functional group. The midsection includes at least one perfluoroalkyl-branched perfluorinated ether unit.

Perfluorinated polyethers (PFPE) as magnetic lubricants

Lubricant with non-terminal functional groups. The location of the functional groups minimizes free chain length and molecular weight of a lubricant while simultaneously maximizing evaporation temperature. The locations of the functional groups to the backbone of the molecule of the lubricant allows for shorter lengths of free backbone length between functional groups attached to a lubricated surface. The lubricant lubricates mechanical devices including hard disk drives. The lubricant can also be added to media or other mechanical parts in conjunction with other lubricants.

Lubricant with non-terminal functional groups

In one embodiment, a magnetic disk medium includes a nonmagnetic substrate, a magnetic recording layer above the nonmagnetic substrate, a protective layer above the magnetic recording layer, and a lubricant layer above the protective layer, the lubricant layer including a mixture of a compound having one or more cyclophosphazene groups and a lubricant formulated R1-OCHCFCFO(CFCFCFO)CFCFCHO&#x2014;R2, wherein R1 and R2 are alkyl chains having at least two hydroxyl groups each, and m is an integer indicating a number of repeating units. According to another embodiment, a magnetic disk medium lubricant includes a mixture of a compound having one or more cyclophosphazene groups and a lubricant formulated as above, such that a magnetic head is provided stable flight above the lubricant layer in conditions having relative humidity of greater than about 40%.

Lubricant layer that provides a stable head-to-disk interface in humid conditions

Fluorinated polytetramethylene glycol (PTMG) with diepoxide endgroups as magnetic lubricants

A batch vapor deposition process for applying adhesion promoter during manufacturing of nanoimprinted discrete track media and bit-patterned media, and mono-molecular layer lubricant on magnetic recording media are disclosed. The adhesion promoter is simultaneously coated on both sides of numerous disk substrates, and minimal solution is wasted. In another step, the lubricant is applied at a uniform thickness that is on the order of a single molecular layer. The lubricant is also applied on the entire disk surfaces while processing multiple disks at a time. Batch processing increases throughput, and vapor lubricant reduces costs compared to conventional techniques. Limited air exposure controls bonding and monolayer adsorption guarantees uniformity.

System, method and apparatus for batch vapor deposition of adhesion promoter for manufacturing discrete track media and bit-patterned media, and mono-molecular layer lubricant on magnetic recording media

Lubricant with non-terminal functional groups. The location of the functional groups minimizes free chain length and molecular weight of a lubricant while simultaneously maximizing evaporation temperature. The locations of the functional groups to the backbone of the molecule of the lubricant allows for shorter lengths of free backbone length between functional groups attached to a lubricated surface. The lubricant lubricates mechanical devices including hard disk drives.

A lubricant composition is provided comprising a first liquid lubricant and a second liquid lubricant, wherein the first liquid lubricant contains a cyclotriphosphazene ring attached to at least one perfluoropolyether having a single terminal hydroxyl group, and the second liquid lubricant contains a perfluoropolyether having two end groups selected from hydroxyl, tertiary amine, and combinations thereof. A magnetic recording media is also provided, comprising a substrate, a magnetic layer, an overcoat layer and a lubricant layer thereon, wherein the lubricant layer is formed from the lubricant composition. A further aspect of the invention concerns a method of making a magnetic recording media comprising forming a magnetic layer on a substrate; forming a protective overcoat layer on the magnetic layer; and forming a lubricant layer on the surface of the overcoat layer by applying the lubricant composition to the surface of the overcoat layer. The lubricant composition is useful for magnetic recording media, especially for magnetic storage hard disk drives, and provides improvements such as substantially reduced lubricant thickness variations when applied to a surface of a hard disk drive.

Lubricant composition for magnetic recording media

A method is presented for controlling process delay times between a) thin film deposition and lubricant application, and b) lubricant application and abrasive polishing. Applicants have discovered that for certain lubricants, a minimum delay time after the overcoat has been deposited before the lubricant is applied increases the number of disks passing the glide test after abrasive polishing. In addition, applicants have discovered that for certain lubricants, the abrasive polishing should take place within a maximum time window following the application of the lubricant. A computerized work-in-progress tracking system is preferably used to implement the method of the invention.

Control of process timing during manufacturing of magnetic thin film disks

A lubricating perfluoropolyether (PFPE) composition for lubricating one or more disks in a disk drive system may be formed by providing a first component of PFPE molecules having an aggregate vapor pressure in the range of 1&times;10 to 1&times;10 atm and a second component of PFPE molecules comprising at least 5% of the total number of molecules of the first component, wherein the second component includes an aggregate vapor pressure lower than that of the first component. The first and second components are mixed together to form a homogeneous composition, which may be in the liquid form. The composition may be introduced into a reservoir in a vapor phase lubricant reservoir system in a disk drive enclosure.

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Gilroy, CA, United States of America

Robert Waltman