The synthesis method of modified polyurethane with ethylene imide and hydrocarbon-hydroxy silicone oil, as well as the application of formaldehyde-free and easy-care finishing agent FS-617 to anti-crease finish of natural fiber are discussed. 讨论了用氮丙环、烃羟基硅油改性聚氨酯制备无甲醛免烫整理剂FS617的合成方法,以及该产品用于天然纤维的抗皱整理工艺条件。