Paper is a desirable substrate for printed electronics as it is low cost and biodegradable and it provides an excellent white background where needed. However, it is very uneven and it has to be thick to have any strength. That may be about to change because strong thin paper now seems a possibility and this advance will probably form a more even surface too.
Scientists at the Swedish Royal Institute of Technology in Stockholm, Sweden have developed a new material called cellulose nanopaper by exposing wood pulp to certain chemicals. Their study found that it has a tensile strength of 214 MPa, making it stronger than cast iron (130 MPa) and nearly as strong as structural steel used in buildings and bridges (250 MPa). Normal paper is flimsy and has a tensile strength less than 1 MPa. They were also able to adjust the paper's strength by changing its internal structure.
The new research may pave the way for applications in construction or as a reinforcing material but also in printed electronics. ACREO, Stora Enso, Toppan Printing, Abu Akademi, Helsinki University, Motorola and others have been developing printed electronics on paper.
Full details can be found in the paper Cellulose Nanopaper Structures of High Toughness.
For more attend Printed Electronics USA 2008.
Source top image: American Chemical Society
Reference: Swedish Royal Institute of Technology
