2017 Volume 53 Issue 12 Pages 415-423
The creep tester using the laser displacement gage which can perform a measurement of a relativedisplacement in non-contact was made. We calculated creep compliance from the measured creep data.Furthermore, by using the numerical analytical approach, we made up the retardation spectrum of the PSAsby carrying out numerical differentiation in logarithmic time. In the SIS/C5 tackifier system, it was examinedwhether the softening point of a tackifier influences the shape of a retardation spectrum.Moreover, we considered the relation between creep compliance and the contact-time dependency of aprobe tack. Creep compliance is an inverse of the elastic modulus which can be found from the amount ofaccumulation deformation, and is the quantity which the PSA flowed or deformed within a certain period. It isrelated to the process in which the PSA contacts to adherend. The deformation process of a PSA is expressedby a retardation spectrum. These creep compliance and retardation spectrums can be regarded as havingevaluated deformation of a PSA required for the contact to adherend. These mechanical properties contributeto the analysis of a tack.
