E Ink is the inventor of several types of electrophoretic ink, often called electronic ink. When laminated to a plastic film, and then adhered to electronics, it creates an Electronic Paper Display (EPD), also known as an ePaper Display. Although futuristic-sounding, electronic ink is actually a straightforward fusion of chemistry, physics and electronics. It's so much like paper, it utilizes the same ink used in the printing industry today.

E Ink JustTint™ is a variable transmissive film, which, when adhered to glass or plastic, allows for control of the light through the surface. JustTint utilizes a one-particle ink system, but drives the ink in new ways versus other ink systems. In JustTint, the black particles move to the side when a charge is applied to allow a transparent area of the capsule.

E Ink’s two particle electronic ink system is made up of millions of tiny microcapsules, each about the diameter of a human hair. Each microcapsule contains negatively charged white particles and positively charged black particles suspended in a clear fluid. When a positive or negative electric field is applied, corresponding particles move to the top of the microcapsule where they become visible to the viewer. This makes the surface appear white or black at that spot.

E Ink Carta™ films utilize this two particle system. 

E Ink Spectra™ 3000 utilizes a three particle ink system in a Microcup® structure. This ink was engineered specifically for Electronic Shelf Labels (ESL) and is offered in black, white and red, and black, white and yellow. This ink system works similarly to the dual particle system, in that a charge is applied to the particles, and to a top and bottom electrode to facilitate movement. However, instead of the use of microcapsules, this system utilizes Microcups®, which are filled with the liquid and sealed.

E Ink Spectra™ 3100 is E Ink’s next generation Spectra product. Spectra 3100 is a four particle ink system which incorporates retailer’s requests for additional color functionality, by utilizing black, white, red and yellow particles to offer vibrant color for rich content. Spectra 3100 has an improved update time, and an expanded temperature range for red and yellow states to satisfy retailers’ needs to operate ESL tags in various environments within their stores. In addition, Spectra 3100 is offered in panels with an updated all-in-one driver IC that supports premium ESLs with higher resolution across various sizes.

E Ink Spectra 6 provides vivid full colors by utilizing four inks system. It's a  revolutionary new color product geared for in-store advertising, indoor signage or any paper sign replacement.

E Ink Spectra 6 features an enhanced color spectrum and an advanced color imaging algorithm to provide full color to improve marketing and advertising performance. 

In 2016 E Ink showcased a multi-particle ink system, Advanced Color ePaper (E Ink ACeP™). The ACeP™ ink platform achieves a full color gamut, including all eight primary colors, by using colored ink particles. The ink can be incorporated into either microcapsule or Microcup® structures. Color is achieved by having all the colored particles in every pixel, removing the need for a color filter array (CFA). ACeP™ maintains the ultra-low power and paper-like readability under all lighting conditions of regular E Ink ePaper.

This system is found in E Ink's Gallery and Prism product lines.