Expanded perlite and chemical blowing agent are the conventionally used density modifier for emulsion explosive. 

The shortcoming of expanded perlite is limited by particle size, strength and oil resistivity, the explosive performance is low and the storage time is short. As for chemical blowing agent, it's not easy to control explosive density, the storage time is short and there is aftereffect.

Since Hollow Glass Microspheres has the characters of low density, low thermal conductivity, low oil absorption, particle size and chemical composition controllable, it's perfectly used as explosive sensitizer. Therefore, the above-mentioned shortcomings can be overcame by adding hollow glass sphere into emulsion explosive, which improves the explosive performance significantly and improves storage stability.