US Patent 7504051 - Purified nanotube applicator liquid

http://www.freepatentsonline.com/7504051.html

This patent from Nantero teaches forming a purified nanotube solution suitable for spin coating processes used in the fabrication of integrated circuits. Claim 1 reads:

1. An applicator liquid for use in an electronics manufacturing process, comprising:

an electronics-grade solvent and a plurality of nanotubes, wherein the applicator liquid is free of polymers and is free of surfactant, wherein the nanotubes are at a concentration of greater than or equal to 10 mg/L, wherein the nanotubes are separated from one another and are distributed in the solvent without precipitation or flocculation and can remain separated for about at least one week;

wherein the nanotubes are pretreated to reduce a level of metal impurities to less than about 1×1018 atoms/cm3, and wherein said applicator liquid is free of particulates having a diameter greater than about 500 nm.