Honcycomb　sandwich　panel　has　the advantage of being light and rigid. By utilizing this aclvantage，the panel has been applied to various kind of industrial products such as aerospace，airplane，railway and building. For further expansion of the application area，the panel production cost is required to reduce. It is indispensable for the realizalion of the lower production cost to reduce in amount adhesives used in the panel.To fulfill the requirement，thus，we have attempted to make a sandwich panel with adhesives dispensed in striped pattern.In this work，the sandwich panel specimens were fabricated bystriped dispensing of acrylic adhesives onto an aluminum plate and an aluminum honeycomb pallet using comb-type trowel. The adhesive strength was also estimated by Peel torque test. It was found then that the striped dispensing provided a large reduction of the adhesive in amounl of ca.40% compared to the conventional whole dispensing with the same adhecsive strength. The adhesive strength was little influenced by difference in the dispensing direction. It was also found that the adhesive successfuliy covered a honeycomb pallet，which is considered to be attributed to the adhesive dispensed in high height on the plate and to the widely spreading of the adhesive on the honeycomb pallet.lt has been demonstrated that the striped dispensing is a useful way to reduce in amount adhesives for produclion of the panel.

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One part epoxy resin is made of liquid epoxy monomer,solid curing agent and filler. And it is transformation from liquid to solid by just heating.This transformation is due to the fact that solid latent curing agent dissolves in liquid epoxy monomer by heat,and a chemical reaction is induced between them.However one part epoxy resin has a critical problems for storage stability since the viscosity increased slowly even under room temperature.This is due to the fact that one part epoxy is premixed liquid monomer and solid curing agent,and they react each other between the interface.Particularly,when imidazole compounds or tertiary amines are used as chain transfer curing agent,storage stability of one part epoxy resin is well known to decrease even under room temperature.Nonetheless,how the molecular structure of curing agent influences storage stability is not clear.Here we clarified the self-assembled structure of long alkyl imidazole as solid curing agent,using X-ray diffraction and FT-IR.It is found that the self-assembled structure of curing agent sharply influenced the storage stability of one part epoxy resin.

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