Watch a Video of talking paper.
Paper Four is a research project at the Mid Sweden University. They are researching how to print electronics such as loudspeakers and keyboards onto paper. They use a recyclable, printable ink to embed paper with the electronics wiring necessary to create the devices. The printable ink acts as the wiring.

In order to create a speaker out of the printable paper, three layers of printed paper are used. The outer layer contains the images and acts as a covering for the paper covered in electronic ink. The middle layer reacts to pressure when the outer layer is pushed and sends a signal to the third layer. The third layer forwards the signal to a chip that activates an audio file. The 'speaker' in the system is a piece of aluminum foil that has had wiring printed on it. The aluminum is spread over an empty cavity in the display.

The researchers hope to use the paper for a variety of applications such as warnings or advertising on product packaging. Their current prototype display looks like something that would be available at a museum.