In April 1997, researchers at the MIT Media Lab (MIT: Massachusetts Institute of Technology) founded the company E Ink to develop an electronic ink technology. The first screen using this technology was available as a prototype in July 2002, and marketed in 2004. Other screens followed for various ebook readers (Librié, Sony Reader, Cybook, Kindle, Nook, etc.), as well as prototypes of flexible displays announcing the forthcoming electronic paper. As explained on the company's website: "Electronic ink is a proprietary material that is processed into a film for integration into electronic displays. Although revolutionary in concept, electronic ink is a straightforward fusion of chemistry, physics and electronics to create this new material. The principal components of electronic ink are millions of tiny microcapsules, about the diameter of a human hair. In one incarnation, each microcapsule contains positively charged white particles and negatively charged black particles suspended in a clear fluid. When a negative electric field is applied, the white particles move to the top of the microcapsule where they become visible to the user. This makes the surface appear white at that spot. At the same time, an opposite electric field pulls the black particles to the bottom of the microcapsules where they are hidden. By reversing this process, the black particles appear at the top of the capsule, which now makes the surface appear dark at that spot. To form an E Ink electronic display, the ink is printed onto a sheet of plastic film that is laminated to a layer of circuitry. The circuitry forms a pattern of pixels that can then be controlled by a display driver. These microcapsules are suspended in a liquid 'carrier medium' allowing them to be printed using existing screen printing processes onto virtually any surface, including glass, plastic, fabric and even paper. Ultimately electronic ink will permit most any surface to become a display, bringing information out of the confines of traditional devices and into the world around us." LCD screens of ebook readers were replaced by E Ink screens. Launched in April 2004 by Sony in Japan, the Librié was the first ebook reader with a 6-inch E Ink screen. Launched in October 2006 in the U.S., the Sony Reader had a E Ink screen that gave “an excellent reading experience very close to that of real paper, making it very easy going on the eyes" (Mike Cook, editor of epubBooks.com). The Sony Reader was then available in Canada, United Kingdom, Germany and France, with various models. The Cybook Gen3 launched by Bookeen in July 2007, the Kindle launched by Amazon in November 2007, and the Nook launched by Barnes & Noble in November 2009 also had E Ink screens.