Composition and process for sealing microcells
The present invention is directed to a composition for the dielectric layer, which composition comprises a mixture of conductive filler material wherein said mixture consists of carbon nanotubes and graphite, and the dielectric layer formed comprises 0.01% to 7% by weight of carbon nanotubes and 0.1% to 20% by weight of graphite. The composition of the present invention may form a dielectric layer which has the desired electrical resistivity. In addition, the dielectric layer is expected to show better barrier properties, less moisture and temperature dependence and improved anisotropic properties.
1. An electrophoretic display device comprising an electrophoretic fluid and at least one dielectric layer, wherein the dielectric layer comprises a mixture of conductive filler materials consisting of carbon nanotubes and graphite, and the dielectric layer comprises 1% to 5% by weight of carbon nanotubes and 3% to 17% by weight of graphite.
2. The device of claim 1 , wherein the dielectric layer comprises 3% to 4% by weight of carbon nanotubes.
3. The device of claim 1 , wherein the dielectric layer comprises 6% to 13% by weight of graphite.
4. The device of claim 1 , wherein the total concentration of carbon nanotubes and graphite in the dielectric layer is less than 18% by weight.
5. The device of claim 1 , wherein the total concentration of carbon nanotubes and graphite in the dielectric layer is less than 14% by weight.
6. The device of claim 1 , wherein the dielectric layer further comprises one or more non-conductive filler materials.
7. The device of claim 6 , wherein the non-conductive filler material is clay, silica, silsesquioxane, polymer particles, or latexes.
8. The device of claim 6 , wherein the ratio of the total weight of the conductive fillers to the total weight of the non-conductive filler in the dielectric layer is in the range of 1:100 to 100:1.
9. The device of claim 6 , wherein the ratio of the total weight of the conductive fillers to the total weight of the non-conductive filler in the dielectric layer is in the range of 5:1 to 30:1.
10. The device of claim 1 , wherein the dielectric layer is a microcell layer.
11. The device of claim 1 , wherein the dielectric layer is a sealing layer enclosing the electrophoretic fluid within microcells.
12. The device of claim 1 , wherein the dielectric layer is an adhesive layer.
13. The device of claim 1 , wherein the dielectric layer is a primer layer.
14. The device of claim 1 , wherein the dielectric layer has an electrical resistivity of 10 7 to 10 10 ohm·cm.