High density information disc lubricants
AssigneeRCA Corporation
InventorsIgal Shidlovsky, William E. Harty
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Abstract
High density information discs comprising a conductive carbon-loaded polyvinylchloride disc is lubricated with a fractionated methyl alkyl siloxane lubricant which contains a long chain alkyl substituted betaine.
Claims8
In a high density information record adapted for use with a playback stylus to effect recovery of signals occupying a bandwidth of at least several megahertz when relative motion at a desired rate is established between said record and said stylus, said record comprising a disc of a conductive material containing an information track constituted by a surface relief pattern in said track to accommodate recovery of signals of said bandwidth upon establishment of relative motion at said rate, said record coated with a methyl alkyl siloxane lubricant having the formula ##STR7## wherein R.sub.1 and R.sub.2 are alkyl groups of 4-20 carbon atoms, x is an integer of 2-4, y is an integer of 0-2 and wherein the sum of x plus y is 4 or less, the improvement which comprises adding to said lubricant a long chain alkyl substituted betaine selected from the group consisting of ##STR8## wherein R.sub.3 is a long chain alkyl group of 6-20 carbon atoms, R.sub.4 is hydrogen or alkyl of 1-3 carbon atoms and z is an integer.
In a capacitance electronic disc having a methyl alkyl siloxane lubricant coating thereon, said lubricant having the formula ##STR11## wherein R.sub.1 and R.sub.2 are alkyl groups of 4-20 carbon atoms, x is an integer of 2-4, y is an integer of 0-2 and wherein the sum of x plus y is 4 or less, the improvement which comprises adding to said lubricant a long chain alkyl substituted betaine selected from the group consisting of ##STR12## wherein R.sub.3 is a long chain alkyl group of 6-20 carbon atoms, R.sub.4 is hydrogen or alkyl of 1-3 carbon atoms and z is an integer.
Dependencies are inferred from the claim text.