Aqueous composition and cleaning method using same

An aqueous composition, comprising:

• (A) from 0.0001 to 10 mass % of at least one compound selected from the group consisting of a C4-13 alkylphosphonic acid, a C4-13 alkylphosphonate ester, a C4-13 alkyl phosphate and a salt thereof, with respect to a total amount of the aqueous composition;
• and
• (B) from 0.0001 to 50 mass % of an acid other than the C4-13 alkylphosphonic acid, the C4-13 alkylphosphonate ester and the C4-13 alkyl phosphate or a salt thereof, with respect to the total amount of the aqueous composition;
• wherein the C4-13 alkylphosphonic acid is present and comprises at least one selected from the group consisting of:
• n-butylphosphonic acid, n-pentylphosphonic acid, n-hexylphosphonic acid, n-heptylphosphonic acid, n-octylphosphonic acid, n-nonylphosphonic acid, n-decylphosphonic acid, n-undecylphosphonic acid, n-dodecylphosphonic acid, and n-tridecylphosphonic acid, optionally in salt form thereof;
• and/or
• the C4-13 alkylphosphonate ester is present and comprises at least one selected from the group consisting of n-butylphosphonate ester, n-pentylphosphonate ester, n-hexylphosphonate ester, n-heptylphosphonate ester, n-octylphosphonate ester, n-nonylphosphonate ester, n-decylphosphonate ester, n-undecylphosphonate ester, n-dodecylphosphonate ester, and n-tridecylphosphonate ester, optionally in salt form thereof.