Phase Diagram (image) Brown University Caption A phase diagram shows the amount of compressive strain needed to create wrinkles, creases and folds in rubbery materials. The purple area denotes the wrinkle state and the aqua areas are two crease states. The spot marked "R" denotes folding. The findings will help engineers control these states and use them in structured nanomaterials. Credit Kim Lab / Brown University Usage Restrictions None Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.