A magnetic disk 10, wherein the first and second fluoropolyethers form individual layers alternately, and interfaces between the individual layers are formed by {HEAD ~ the ionic bonding} through {TAIL ~ salt formation} of the acidic terminal groups and the basic terminal groups 
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A magnetic disk 10 , wherein the first and second fluoropolyethers form individual layers alternately , and interfaces between the individual layers are formed by { HEAD ~ the ionic bonding } through { TAIL ~ salt formation } of the acidic terminal groups and the basic terminal groups
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH