A detergent action of polyethylene oxide(PEO) on the wet soiling of hydrophobic fiber-hydrophilic soil was studied. Molecular weights of PEO were 0.46×<10>^6 and 3.54×<10>^6. The carbon black oxidized by Donnat method was used as a hydrophilic soil ; Polyester and polypropylene as hydrophobic fibers. The adsorption of PEO on fiber and carbon surfaces was observed by contact angle and ζ-potential measurements. The deposition of carbon black onto polyester was prevented by PEO, while in the PEO concentration below 0.005g/100ml it was promoted onto polypropylene. The adsorption amounts of PEO on polyester and polypropylenewere 1×<10>^<-10> mol/<cm>^2 and 2x<10>^<-10>mol/<cm>^2, respectively. They were independent of the molecular weight of PEO. In PEO-18N(M.W.3.54×<10>^6), the immobile layers resulted from polymer adsorption were reached 1000Å or abave.
In conclusion, it was found that the hydration effect of adsorbed PEO might play major role either for soil deposition or for soil prevention.