Microstructures were produced on curved surfaces and micro-protrusions by using direct micromolding with fourthermoplastic polymers. This method is simpler and more convenient than micromolding with liquid prepolymer or using theμTM method. By repeated molding

crossed structures were produced with a stamp prepared only with lines. The processingvariables including the softening temperature of the polymers and heating time were discussed. The result shows that the optimal molding temperature is preferably slightly higher than the melting temperature of the thermoplastic polymers

at which polymers are in the critical states of being melted.This method can be applied to many polymers except those with high softening temperatures or high rate of shrinkage upon temperature change.