To evaluate the shearing properties of pressure sensitive adhesive (PSA) in the micro deformation range, a higher resolution test apparatus has been developed. The test apparatus can measure the micro displacement caused by a shear load with maximum resolution of 0.08 nm by specification of laser interferometer. By this apparatus, the shear displacement of an acrylic PSA was measured under very low shear load. The influences of cross-linking agent ratio of the specimen and the adherend temperature on the micro shear properties were evaluated as static shear properties using the coefficients of viscoelastic model. As a result of statistical analysis, the interaction between the cross-linking agent ratio and adherend temperature properties became highly loading time dependent.In addition, the dynamic test with bulk specimens was carried out for comparison with the static shear properties using the new test apparatus. In the exponential displacement stage, which is characterized by elastic and viscosity behavior, adherend temperature dependence of the static shear property is approximately shown similar profiles to the effects caused by measurement temperature for storage and loss modulus by the dynamics viscoelastic test. By these results, it has bee nsuggested that the new test apparatus is useful for evaluating the micro shear properties of PSA with loading time.

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The stress-strain curve of the cross-linked acrylic pressure sensitive adhesive (PSA) was measured by a tensile test at various strain rate.From the detail observation of the stringiness behavior of PSA at peeling,the strain and strain rate for stringiness were determined in the same way as the previously reported method. From correspondence of these two results,the internal stress generated in the fibril of stringiness at peeling was able to be calculated.This internal stress means that in the nonequilibrium state at peeling of PSA. We established the method to determine the internal stress using the strain rate even if in the unsteady state at peeling of PSA.The peeling rate was changed dependent on the adherend.However,the internal stress of PSA was found to be almost constant dependent on the applied peeling load.

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For the purpose of controlling fossil resources and reducing hot press temperature for making wood based materials,Tannin-Phenol-formaldehyde (TPF) resin were synthesized with the mimoza tannin of the natural product which included plentiful in the bark of the acacia species.Curing behavior of the synthesized TPF resins was analysed by using a thermo-mechanical analysis (TMA) spring method and examined the bonding property of the plywood with various TPF resins.The 30% TPF and 50% TPF for molar ratio (F/P) 1.2 and 1.4 for phenol replaced of the mimoza tannin were reducedcuring temperature.The resin of molar ratio 1.4 was cured lower curing temperature than that of molar ratio l.2 and a good adhesion performance were recognized.

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