Sun Chemical Corporation

University of Cincinnati

April Milarcik

Jason C Heikenfeld

Russell J Schwartz

Lisa Clapp

Stanislav G Vilner

George H Robertson

Bo Sun

Manjeet Dhindsa

Stephanie Chevalliot

Colored fluids for electrowetting, electro fluidic, or electrophoretic devices, and the devices themselves, are disclosed. The colored fluid can include a nonaqueous polar solvent having (a) a dynamic viscosity of 0.1 cP to 50 cP at 250 C, (b) a surface tension of 25 dynes/cm to 55 dynes/cm at 250 C, and (c) an electrowetting relative response of 40% to 80%. Such colored fluids further include a colorant selected from a pigment and/or a dye. In another embodiment, the colored fluid can include a non-polar solvent and an organic colorant selected from a pigment and/or a dye. Such colored fluids can be black in color and have a conductivity from 0 pS/cm to 5 pS/cm and a dielectric constant less than 3. The use of the colored fluids offers improvements in reliability, higher levels of chroma in the dispersed state, and the ability to achieve higher contrast ratios in display technologies.

Colored fluids for electrowetting, electrofluidic, and electrophoretic technologies

Colored conductive fluids for electrowetting or electrofluidic devices, and the devices themselves, are disclosed. The colored conductive fluid includes a polar solvent and a colorant selected from a pigment and/or a dye. The polar solvent has (a) a dynamic viscosity of 0.1 cP to 1000 cP at 25&#xb0; C., (b) a surface tension of 25 dynes/cm to 90 dynes/cm at 25&#xb0; C., and (c) an electrowetting relative response of 20% to 80%. The colored conductive fluid itself can have an electrical conductivity from 0.1 &#x3bc;S/cm to 3,000 &#x3bc;S/cm and can have no greater than 500 total ppm of monatomic ions with ionic radii smaller than 2.0 &#x212b; and polyatomic ions with ionic radii smaller than 1.45 &#x212b;. The colored conductive fluid should not cause electrical breakdown of a dielectric in the device in which it is employed. An agent for controlling electrical conductivity can optionally be added to the colored conductive fluid.

Colored conductive fluids for electrowetting and electrofluidic technologies

Electrofluidic devices, visual displays formed from the electrofluidic devices, and methods for making and operating such electrofluidic devices Each electrofluidic device has a fluid vessel with first and second regions that contain an electrically conductive polar fluid and a non-polar fluid The polar and/or the non-polar fluids are externally visible external through a viewable area of the second region A voltage source is electrically connected to a capacitor having a hydrophobic surface that contacts the polar fluid and provides a first principal radius of curvature of the polar fluid that is convex and smaller than a second principal radius of curvature of the polar fluid in the first region The voltage source applies an electromechanical force to the polar fluid, thereby transferring the polar fluid from the first region to the second region and causing a spectral property of light transferred through the viewable area to change.

Electrofluidic devices, visual displays, and methods for making and operating such electrofluidic devices

Growing community of inventors

Cincinnati, OH, United States of America

April Milarcik