Foundations in Graphic Communications: Checking Color Proofs  
Electronic Ink (I): Ingredients
Cross Section of Electronic Ink (e-ink) Microcapsules

• being developed by E-Ink (Cambridge, MA) and Xerox/PARC (Palo Alto, CA)

• e-ink can be applied to any surface (using screen-printing techniques)

• components:
1. "microcapsules" (100,000 per square inch of paper)
2. ink or oil medium filling the microcapsules
3. electrically charged, pigmented chips or balls inside the microcapsules

• chips are black, white, or black & white

• apply electric charge to printed surface

• chips rise, fall, or rotate within the microcapsules, creating light/dark patterns that form words and images