Provided is an information processing apparatus including a display device including a display screen, a communication circuit which, in operation, exchanges information with plural portable terminals, and a control circuit connected to the display device and the communication circuit, in which the display screen includes a display area having a plurality of partial display areas in a plurality of separate regions of the display screen, each of the partial display areas being associated with a different one of the portable terminals, and the control circuit, in operation, displays, in each partial display area of the partial display areas, information communicated via the communication circuit with the one of the portable terminals associated with the partial display area.

The present disclosure relates to a system comprising a writing instrument. The writing instrument comprises an ink. wherein the ink comprises a coloring agent and a bonding agent. The adhesiveness of the bonding agent can be altered by applying a voltage or a voltage and a current. Further. the system comprises a writing surface comprising a first electrode and a second electrode or a writing surface comprising a first electrode and an erasing tool comprising a second electrode.

The heating eraser for removing thermally changeable ink comprises a heating eraser unit that removes or changes a color by instantaneously applying heat at 50 to 65 C. as a color changing temperature range of a phase transition material selectively along a handwriting written or drawn by a writing instrument using the thermally changeable ink containing thermally changeable fine particles of 10 wt % to 70 wt % including a core portion containing the transition material including a phenol-based compound containing an aliphatic functional group having carbon atoms of 6 or more and a shell layer covering the core portion and made of a polymer resin on a substrate.

A system comprises a writing instrument. The writing instrument comprises an ink, wherein the ink comprises a coloring agent and a bonding agent. The adhesiveness of the bonding agent can be altered by applying a voltage or a voltage and a current. Further, the system comprises a writing surface comprising a first electrode and a second electrode or a writing surface comprising a first electrode and an erasing tool comprising a second electrode.