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Study of Curing Behavior of Urethane Clear for Short Baking

Article of Honda R&D Technical Review Vol.29 No.2


Curing behavior required for polishing repair of the clearcoat has been studied with the aim of shortening the baking time for reducing CO2 emissions in the coating process. The authors also studied curing behavior that enables the transition of Isocyanate to the basecoat from the clearcoat.
As a result, it was found that polishing repairability is enhanced by increasing the storage modulus of the clearcoat at the end of baking. Furthermore, it was found that there is a correlation between the time until the storage modulus rises and transition amount of isocyanate to the basecoat. The curing behavior required for a shorter baking time and directivity in resin design were determined from these results.


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Author (organization or company)

Takanori HASHIMOTO(Automobile R&D Center)

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