Polyglycerol alkyl ether type nonionic surfactant

A nonionic surfactant composition, comprising:

• 70 to 95 percent by weight of a polyglycerol alkyl ether nonionic surfactant, wherein the polyglycerol monoalkyl ether is a polyglycerol monoalkyl ether of following formula (1):
• wherein:
• R represents a branched-chain aliphatic hydrocarbon group having from 14 to 22 carbon atoms;
• “n” denotes an average number of repeating glycerol units ranging from 2 to 10;
• and repeating unit C3H6O2 in the parentheses have both structures of following formulae (2) and (3):
• —CH2—CHOH—CH2O— (2)
• —CH(CH2OH)CH2O— (3);
• and
• 5 to 30 percent by weight of water,
• wherein the polyglycerol alkyl ether nonionic surfactant comprises one or more polyglycerol alkyl ethers, and
• wherein the nonionic surfactant has a polyglycerol monoalkyl ether content of 75 percent by weight or more and a polyglycerol dialkyl ether content of 5 percent by weight or less.