Surfactant, process for producing the same, and detergent composition

A process for producing an aliphatic alcohol alkylene oxide adduct,

• which comprises addition reaction of an aliphatic alcohol alkylene oxide adduct (e), obtainable by adding 1-2.5 moles on the average of an alkylene oxide (b2) containing at least two carbon atoms to an aliphatic alcohol (a2) containing 1-24 carbon atoms in the presence of a catalyst (d) providing an adduct having a distribution constant c′ of 1.0 or less as determined by the following equation (4′),
• with an alkylene oxide (b3) containing at least two carbon atoms in the presence of an alkaline catalyst (f):
• c′=(v′+n0′/n00′−1)/[Ln(n00′/n0′)+n0′/n00′−1] (4′)
• wherein v′ represents the average addition molar number of alkylene oxide added per 1 mole of the aliphatic alcohol (a2), n00′ represents the molar number of the aliphatic alcohol (a2) used in the reaction, and n0′ represents the molar number of the aliphatic alcohol (a2) unreacted.

An anionic surfactant obtainable by anionization of an aliphatic alcohol alkylene oxide adduct (A′),

• said (A′) being directly produced by adding an alkylene oxide (b1) to an aliphatic alcohol (a1) and satisfying the following (ii′), (iii′) and (iv):
• (ii′) having a ratio Mw/Mn of a weight-average molecular weight (Mw) to a number-average molecular weight (Mn) satisfying the following relation (2′) or (3′):
• Mw/Mn≦0.030×Ln(v″)+1.010 (in case of v″<10) (2′) Mw/Mn≦−0.026×Ln(v″)+1.139 (in case of v″≧10) (3′)
• wherein v″ represents the average of (m′+n′+p′) in the following general formula (1′);
• (iii′) having a distribution constant c″, determined by the following equation (4″), of 1.0 or less, this being required only in case of v up to 12:
• c″=(v″+n0/n00−1)/[Ln(n00/n0)+n0/n00−1] (4″)
• wherein v″ is the same in the above, n00 represents the molar number of the aliphatic alcohol (a1) used in the reaction, and n0 represents the molar number of the aliphatic alcohol (a1) unreacted;
• and
• (iv) comprising one compound represented by the following general formula (1′), or a mixture of two or more thereof:
• R1O—[(C2H4O)m′/(AO)n′]—(C2H4O)p′—H (1′)
• wherein R1 is an aliphatic hydrocarbon group containing 8-24 carbon atoms or a cycloaliphatic hydrocarbon group containing 8-24 carbon atoms;
• A is an alkylene group containing at least 3 carbon atoms;
• m′ is 0 or an integer of 1 or more, the average thereof being in the range of 0-5, n′ is 0 or an integer of 1 or more, the average thereof being in the range of 0-5, p′ is 0 or an integer of 1 or more, the average thereof being in the range of 0-10, (m′+n′+p′) is an integer, the average thereof being in the range of 1-20, and average of (m′+p′)/(m′+n′+p′) is at least 0.5;
• and, in case of m′≠0 and n′≠0, {(C2H4O)m′/(AO)n′} represents block addition or random addition;