Fluorescent Brightening 'Agents (FBA's) was built in powder soap and synthetic detergents as early as 1955 in Japan. Since then coverage of the syndet is steadily increasing up to 95%.
Quite recently, revival of the powder soap exhibits a queer tendency to reject the addition of FBA's.
In this respect, the authors examined the FBA's effect in newly prevailing commercial soaps in comparison with that in synthetic detergents, and reached a conclusion that some powder soaps should accept the FBA formulation to increase the whiteness of cellulosic washing materials.