| 摘要 |
PROBLEM TO BE SOLVED: To prevent a modified 2,5(6)-diisocyanatomethylbicyclo[2,2,1]heptane (NBDI) from discoloration under extremely strong irradiation of ultraviolet rays for long hours by using as an effective ingredient an orthocarboxylate ester compound. SOLUTION: As orthocarboxylate ester compounds are preferable orthoformate esters such as trimethyl orthoformate, triethyl orthoformate, tri-n- propyl orthoformate, tri-iso-propyl orthoformate, tri-n-butyl orthoformate, tri-sec- butyl orthoformate, tri-tert-butyl orthoformate and the like. As a modified NBDI is preferable an isocyanurate ring-containing polyisocyanate obtained by trimerizing NBDI. The orthocarboxylate ester compound is used in an amount of about 0.0001-20 wt.% based on the (modified) NBDI.
|
