| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject composition having excellent storage stability and useful for various foamable and non-foamable polyurethanes by bringing the composition to contain a specific methylenebis(phenyl isocyanate) component and ureton imine in a specific ratio. SOLUTION: This composition comprises about >=90.0 wt.% of (A) methylenebis(phenyl isocyanate) (abbreviated as MDI) component containing at least about 90.0 wt.% of 4,4'-MDI and (B) about <5.0 wt.% of ureton imine. The ingredient B is preferably produced by converting an organic isocyanate to a carbodiimide using a catalyst capable of converting the carbodiimide to a ureton imine (preferably a phosphate, or the like, such as triethyl phosphate) in the presence of excessive 4,4'-MDI. The organic isocyanate preferably contains >=45 wt.% of 4,4'-MDI and the rest of 2,4'-MDI and other MDI isomers.
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