The solubilizer is a C1-3-monoalkyl ether of mono-, di- or tripropylene glycol, a methyl ether acetate of mono-, di- or tripropylene glycol or a dimethyl ether of mono-, di- or tripropylene glycol.

The hydrophilic co-solvent may be selected from the group consisting of propylene glycol n-propyl ether, tripropylene glycol methyl ether, and dipropylene glycol methyl ether.

Provided is a method for producing di- and/or tripropylene glycol, the method comprising the following steps (A), (B), (C), (D), and (E).

Application: Propylene glycol is used primarily in the manufacture of unsaturated polyester resins, as well as in the manufacture of dipropylene glycol and tripropylene glycol; it is also a component of many products such as:

A cleaning composition comprises a (1) mono-, di- or tripropylene glycol n-butyl ether, (2) a solubilizer and (3) from 35 to 95 percent of water, based on the total weight of the cleaning composition.