The effect of curing condition such as curing time, curing humidity and adhesive thickness on an adhesivestrength of one-component moisture curable cyanoacrylate adhesive was investigated experimentally. Thefracture surface of adhesively bonded joint was also observed to investigate curing time influence. A stresswhen the single lap joint was fractured under tensile test was defined as the adhesive strength. The adhesivestrength was measured from 10 minutes to 168 hours after being adhered. Gel cyanoacrylate adhesive of whichcuring time is slow was used to investigate adhesion process. A structural rolled steel SS400 was adaptedas adherends which were adhered to make a single lap joint for a tensile test. The adherend surface wasfabricated by milling and grinding process. The time between adhesive coating and adherend assembling wasobserved to avoid the effect of that time.The polymerization reaction of cyanoacrylate during curing was also investigated. The adhesion was coated0.02mm thickness on a specimen. The Ramen intensity of C=C（ double coupling） of which wavenumbers isaround 1620 cm-1 in the adhesive was observed by using Infrared absorption spectrum and Ramen scatteringspectrum methods. The correlation among the measured intensity, the adhesive strength and the curing timewas identified by the analyzation of these coupling processes of adhesion and the tensile test of the single lapjoint.

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.