US Patent 7652098 - GHz circuit board made frm CNT resin

http://www.freepatentsonline.com/7652098.html

High frequency electronic circuitry requires low dielectric material to minimize signal attenuation. This patent teaches a circuit board formed from carbon nanotube composite material providing the required low signal loss. Claim 1 reads:

1. A resin composition for GHz-band electronic components, the composition comprising

nanoscale carbon tubes and

at least one resin selected from the group consisting of thermoplastic resins, curable resins, and composite resins of thermoplastic resins and curable resins,

wherein the nanoscale carbon tubes are present in an amount of 0.0001 to 0.4 wt. % based on the resin,

wherein the nanoscale carbon tubes are: (ii) amorphous nanoscale carbon tubes; (iii) nanoflake carbon tubes; (iv) iron-carbon composites each composed of (a) a carbon tube selected from the group consisting of nanoflake carbon tubes and nested multi-walled carbon nanotubes, and (b) iron carbide or iron,

wherein the iron carbide or iron (b) fills 10 to 90% of the internal space of the carbon tube (a); or (v) a mixture of at least two of (ii) to (iv).