An alkylene oxide derivative represented by following formula (I):R—；O-(AO)a—；[(PO)b/(EO)c]—；H ； ；(I)(R represents a linear or branched alkyl group having from 4 to 36 carbons； AO is an oxyalkylene group having three or four carbons, PO is an oxypropylene group, and EO is an oxyethylene group； a, b, and c are the average addition molar numbers of the oxyalkylene group, the oxypropylene group, and the oxyethylene group per molecule, respectively, and 1≤；a≤；40, 1≤；b≤；40, 1≤；c≤；80, and (a+b+c)≥；20； [(PO)b/(EO)c] represents a polyoxyalkylene group in which b moles of PO and c moles of EO are bonded randomly, and the random rate x is 0.1≤；x≤；1).
