Abstract
To investigate the detergency of nonionic surfactant, following two parts of experiments were carried out for the polyoxyethylene nonylphenyl ether EO 10mole (PEG-N) by using Launder-O-meter and artificial standard soiled cotton cloth.
1) The effects of inorganic builders on soft and hard water.
The concentration of PEG-N aqueous solutions was from 0.05g/l to 0.5g/l and that of inorganic builders was twice of the surfactant.
The result showed that polyphosphates (hexametaphosphate, tripoly phosphate and pyrophosphate), were more effective than other builders (silicate, carbonate and neutral salts) in both soft and hard water.
2) The influence of calcium salt present in the washing water.
The detergency test was carried out in water of various hardness, fixing the concentration of PEG-N aqueous solution at 0.1g/l. As a result, it was found that in the case of polyphosphate, there was certain relationship between the concentration of added builders and washing efficiency.
For example, in the case of pyrophosphate, when 0.5 mole of pyrophosphate per 1mole of calcium ion was used, washing power increased remarkably.
