and 5 mols of ethylene oxide was esterified with phosphorus pentoxide to obtain phosphoric ester containing monoester compound at a content of 80 four and one half 4 5 parts of the above phosphoric ester and 30 parts of perchloroethylene were added to 90 parts of tris 2 3 dibromopropyl phosphate and mixed uniformly at 40 u00b0 c then 33 parts of water was added to the resultant mixture with continuous stirring by homomixer to obtain 157 5 parts of homogeneous milk white emulsion the obtained emulsion was very stable after standing for a long time and then 26 parts of the above emulsion was diluted with water to 100 parts to form a flame retarding treatment bath polyester taffeta was soaked in a bath of the resultant treatment liquid and squeezed to wet pick up 65 then this treated polyester taffeta was dried at 120 u00b0 c for 5 minutes for controls various treatment baths were prepared by emulsification of tris 2 3 dibromopropyl phosphate with different amounts of the above phosphoric ester and with other conventional surfactants polyester taffeta was treated with each treatment bath in the same manner as the above each treated cloth was measured its flammability by the.