The lifetimes of stressed lap joints of stainless steel plates (1.5mm thickness) bonded by one-liquid type and two-liquid type epoxy adhesives,the gradient of stress-life time curve increasing with decreasing life time of 5.5 MPa which is high stress range. The other side, life time of two-liquid type adhesives is shorter than that of one-liquid ones in the high stress range, but in the low stress range life time of former ones is larger than that of latter ones.

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Epoxy resin compounds modified with aromatic olefin oligomers for electronic materials were prepared and the properties were studied. Cured compounds modified with aromatic olefin oligomers have been found to be decreased water-absorbing capacity and dielectric constant. As aromatic olefin oligomers, styrene oligomers and indene oligomers were synthesized. Properties of cured systems with indene oligomers were better than that with styrene oligomers,　i.e., linear expansion of cured systems with indene oligomers was lower than that with styrene oligomers, and temperature of inflection point in TMA of the former was higher than that of the latter. The phase structures of cured systems were analyzed by relationships between tanδ and temperature. As the results, we found that water-absorbing capacity and　dielectric constant of cured systems with indene oligomers decreased without decrease of linear expansion. We considered that the reason why cured systems with indene oligomers showed above good properties was due to the rigid molecular structure of indene oligomers and the good compatibility to cured epoxy resin matrix.

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Thispaperisconcernedwithbondingstrengthoftheadhesivetapecomposedofanacryliccopolymer,mixedepoxyresinsanddipentaorithrytolhexaacrylate(DPHA),whichisapplicabletodicinganddiebondingthereafter.Investigatedweretheeffectsoftheexposuredoseofultra-violetlight(UV)beforedicingandtheamountsofDPHAonthebondingstrengthbetweenthermallycuredadhesivecompoundandthecoppersubstrateasthemodelfoi､oil℃uits･IncaseswhereeitheroftheexposureandDPHAwaswithin400mJ/cm-or10partsofothercomponents.respectively,the90peelstrengthwasstrongenoughexceeding6N/cm.ThestoragemodulusatiOU℃,theinitialbondingtemperature,wasbelow4x10'Paevenforthecasesofpooradhesion,indicatingenoughwettabilitytothesubstrate.However,theX-rayphotoelectronspectrometry(XPS)takenatatake-offangleof45ontheinterfacelayerofadhesivesprovedthattheoxygen/carbonatomicratio(O/C)was0.36beforeUVexposureandthendecreasedto0.27uponexposureto780mJ/cm-resultinginverypooradhesion.ThetendencyofdecrementofoxygenatomsintheinterfacewasalsoobservedinthecaseofhigherDPHAcontentthan10parts.Itwasthereforeconcludedthatthebondingstrengthlargelydependsonthechangeindistributionofoxygenatomsorpolargroupsintheinterfacelayet･duringUVcuringofDPHA.

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