That is, the structural mechanism of letting transparent soap be transparent is considered that opaque soap fibrous
microcrystals, which are optically discontinuous in size with respect to visible light, are mainly severed perpendicularly to the fiber axes by the addition of the above-described sugars and polyols and refined to the size of a wavelength of visible light or less; as a result, the soap becomes transparent. There fore, the hardness and the solidification point easily decrease compared with the soap in which sugars and polyols are not added.