However, the quality of the SPR formula was
determined by the suitable particle and detergent
components and their appropriate concentrations in
the suspension. For example, molybdenum disulfide
and tergitol NP-7 were used as the particle and the
detergent in SPR I, II and III. SPR II and SPR III
were effective solutions, with proportions of particle
to detergent of 13.1 and 13, respectively, whereas that
of SPR I was 12.5. The important factors that affect
the quality of SPR are the type of particle, detergent
and their proportion.