SWeNT’s IP estate currently consists of 30 issued U.S. and foreign patents. Several
pending applications are currently undergoing prosecution.
Six U.S. patents form the primary core of SWeNT’s patent protection. These patents are
listed below with a brief summary of the most important claim for each patent.
U.S. Patent No. 6,955,800, issued on October 18, 2005, termination date June 2, 2020.
This claim is not limited to the production of single-walled nanotubes.
U.S. Patent No. 7,563,428, issued July 21, 2009, termination date September 3, 2019.
Claims 1 and 27 are the significant claims in this patent. Claim 1 provides a method
for selectively producing single-walled carbon nanotubes. The claimed method utilizes
catalytic particles comprising at least one Group VIII metal, excluding iron, and least
one Group VIb metal selected from the group consisting of molybdenum and tungsten.
The catalytic particles are placed in a reactor and combined with a carbon containing
gas at a temperature sufficient to catalytically produce a solid carbon product. Single-
walled carbon nanotubes makeup 80% or more of the product while 20% or less of the
product is amorphous carbon, graphite or multi-walled carbon nanotubes. Claim 27 is
similar to claim 1 but adds a further limitation of requiring a support material selected
from the group consisting of silica, silicon, mc-41, alumina, magnesium oxide, aluminum
stabilized magnesium oxide, zirconium oxide, molecular zeolites, oxidic supports,
quartz, glass, and oxidized silicon surfaces. Further, claim 27 provides that the resulting
catalytic product is primarily carbon nanotubes with less than 10% of the final product
being graphite and an amorphous carbon. Thus, claim 27 is arguably broader in scope, as
it does not limit the method to the production of single-walled carbon nanotubes. Rather,
claim 27 can be read to cover the production of both single-walled and multi-walled
U.S. Patent No. 6,962,892, issued November 8, 2005, termination date September 3, 2019.
This patent is directed to metallic catalytic particles for producing single-walled carbon
nanotubes. In particular, claim 1 covers the catalyst material used to make single-
walled carbon nanotubes. Claim 1 provides a catalytic product comprising cobalt and
molybdenum in a ration of 1 to 2. These metals are carried by a support material thereby
forming the catalytic particle. The claim further requires single-walled carbon nanotubes
deposited on the catalytic particle. Thus, the claims of this patent are directed to a
catalytic product carrying single-walled carbon nanotubes.
U.S. Patent No. 6,333,016, issued December 25, 2001, termination dated September 3,
This patent is directed to a method of producing carbon nanotubes. In particular, the
patent describes methods for producing quantities of single-walled carbon nanotubes by
the catalytic reaction of a carbon containing gas with a bimetallic particle. The broadest
claim of the patent is claim 1. According to claim 1, the method comprises the selective
production of single-walled carbon nanotubes by contacting metallic catalytic particles
comprising cobalt and molybdenum in a ratio of one part cobalt to at least two or more
parts molybdenum with a carbon containing gas at a temperature sufficient to selectively
produce single-walled carbon nanotubes. At least 80% of resulting carbon containing
product is in the form of single-walled carbon nanotubes.
U.S. Patent No. 6,919,064, issued July 19, 2005, termination date June 2, 2020.
This patent is directed to processes for producing single-walled carbon nanotubes.
Claims 1 and 12 are the broadest claims in this particular patent. Both claims describe
a process wherein catalytic particles comprise a support material. The catalytic
particles are placed within a reactor and exposed to a carbon containing gas to produce
single-walled carbon nanotubes on the catalytic particles. Claim 1 includes a step of
removing air from the catalytic particles by exposing the particles to a heated inert
gas. Subsequently the particles are reduced by exposure to a heated producing gas. In
contrast, claim 12 omits the step of removing air and describes the reduction as a single
step of treating the catalytic particles with a reduction process.
U.S. Patent No. 7,816,709, issued October 19, 2010
The claims in this patent are directed to a nanotube-ceramic composite. The ceramic
corresponds to the support material used for the catalyst composition. The typical
support is silica. The nanotube-ceramic composite can be used "as prepared" without
further purification providing significant cost advantages.
Provisional Application Ser. No. 61/267170, filed on December 7, 2009
This application is directed to the use of carbon nanotubes in sensors. In particular, the
disclosure discusses the use of CNT in stress/strain sensors.
U.S. Patent No. 7,842,387 issued November 30, 2010
This application is directed to a method for growing carbon nanotubes and in particular
single-walled carbon nanotubes on a flat substrate, such as a silicon wafer, and
subsequently transferring the nanotubes onto the surface of a polymer film or separately
harvesting the carbon nanotubes from the flat substrate.
U.S. Patent Application Ser. No. 12/938,109, filed November 2, 2010 (divisional
application of U.S. Ser. No. 11/450,642)
This application is a divisional of Ser. No. 11/450642. As such the specification is
identical to the parent application. The pending claims in the divisional application
describe a method of preparing a bi-layer composition of carbon nanotubes on a flat
U.S. Patent No. 7,829,622, issued January 9, 2010
The claims describe a method of preparing a carbon nanotube-polymer composite.
PCT Application No. PCT/US10/42321 filed July 16, 2010
This application claims the benefit of U.S. Provisional Application Ser. No. 61/226,438
(expired). The claims describe catalyst compositions.
The issued patents within the SWeNT IP estate cover the current SWeNT manufacturing process
for preparing single-walled carbon nanotubes. Additionally, several of the patents include claims
that are broad enough to include the production of multi-walled carbon nanotubes. Further,
SWeNT continues to develop new techniques and catalysts for carbon nanotube manufacture.