US Patent 7524746 - High refractive index semiconductor nanocrystal material

http://www.freepatentsonline.com/7524746.html

In order to increase the light extraction efficiency for LED lighting this patent from Evident Technologies teaches a semiconductor nanocrystal material used as an LED encapsulent formed with a high refractive index to minimize scattering and absorption. Claim 1 reads:

1. A high-refractive index material comprising at least one semiconductor nanocrystal composition incorporated in a matrix material, wherein the high-refractive index material has a refractive index greater than 1.5, and wherein the semiconductor nanocrystal composition comprises: (1) a semiconductor nanocrystal core comprising a II-VI, III-V, or IV-VI semiconductor material, the semiconductor nanocrystal core having an outer surface; and (2) a metal layer grown on the outer surface of the semiconductor nanocrystal core, the metal layer having an outer surface.

US Patent 7482059 - Semiconductor nanocrystal with metal coating

http://www.freepatentsonline.com/7482059.html

This patent from Evident Technologies teaches a solution to a problem of oxidation of semiconductor nanocrystals (quantum dots) that can reduce the fluorescence properties over time by providing a protective metal coating. Claim 1 reads:

1. A semiconductor nanocrystal complex comprising:

a semiconductor nanocrystal core having an outer surface and having a diameter between 1 nanometers and 20 nanometers; and

a metal layer formed on the outer surface of the semiconductor nanocrystal core after synthesis of the semiconductor nanocrystal core, wherein no linking molecules are used to attach the metal layer to the core.

US Patent 7399429 - III-V nanocrystal with >25% quantum efficiency

http://www.freepatentsonline.com/7399429.html

This patent from Evident Technologies teaches a metal coated nanocrystal composition with high quantum efficiencies. Although earlier quantum dot core-shell structures with similar efficiencies were earlier patented (see US 7,125,605) the metal coating in this configuration offers the advantage of increased chemical stability. Claim 1 reads:

1. A semiconductor nanocrystal complex comprising:

a semiconductor nanocrystal core comprising a III-V semiconductor material, and

a metal layer formed on at least a portion of an outer surface of the semiconductor nanocrystal core, wherein the semiconductor nanocrystal complex is electronically and chemically stable with a luminescent quantum yield of at least 25%.

US Patent 7341734 - Skin or hair care products formed using semiconductor nanocrystals

http://www.freepatentsonline.com/7341734.html

There is some controversy over the use of nanostructured material in products designed to interact with bioorganisms. However, there are a large variety of such products available such as sunscreens and cosmetics. This patent from Evident technologies presents some basic claims to the use of semiconductor nanocrystals such as ZnO in such products. Claim 1 reads:

1. A personal care composition comprising: a personal care ingredient; and a semiconductor nanocrystal dispersed or dissolved in the personal care ingredient, the semiconductor nanocrystal having a diameter between one and twenty nanometers.

However, some prior art may have been overlooked during the examination such as US 6403653 or US 2005/0265935.