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The durability and transfer properties of several replica molds were evaluated. Replica molds with patterns of holes or pillars were fabricated by ultraviolet nanoimprint lithography (UV-NIL) from an epoxy-type UV-curable resin. The resin had an antifouling effect, permitting the fabrication of replica mold without the use of a release agent. The transfer properties of the molds were evaluated by contact-angle measurements on the mold and by scanning electron microscopy of the UV-NIL transferred pattern. The error rates were calculated from the scanning electron micrographs and the values was used to assess the lifetimes of the replica molds. The thickness of the residual layer of the replica mold was controlled by changing the roll-press method. A replica mold with a thick residual layer showed a longer lifetime than one with a thin residual layer. In addition, the use of a cushion material was effective in improving the lifetime. Molds with hole patterns showed a longer lifetime than those with pillar patterns, and a lifetime of around 1000 repetitions was achieved.

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High-Polymer and rubber are important materials. Evaluation method of stress-strain behavior of them is demanded in order to use them with reliability. But it is difficult especially in unloading process and in fatigue. And the mechanical properties of high-polymer and rubber are deteriorated more easily than that of metal. The constitutive equation that can consider the deterioration and that can evaluate deformation in unloading process is demanded. Nitrile Butadiene Rubber (NBR) is hard rubber used as O-ring and gasket, etc. In this study, the deterioration tests of NBR in water at 60C for 0 month, 3 months, 7 months, 9 months and 12 months were carried out. Compression tests of NBR in water at 25C were carried out with deteriorated material. VBO model, one of constitutive equation, is applied to evaluate the deformation of them. The mechanical properties used in VBO model were taken from the constant-strain-rate tests and relaxation tests. And the influence of deterioration to mechanical properties used in VBO model was obtained. The stress-strain curve simulated with VBO model well corresponded to that of test in loading process, but didn't in unloading process. Therefore we improved VBO model with the strain acceleration term. We showed the probability that the improved model could evaluate the stress-strain behavior in unloading process.

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