Small Particle Reagents are suspensions of a powder in water with a detergent. The powder particles adhere to a fingerprint as does a fingerprint powder
SPR Black is a suspension of molybdenedisulfide powder in water with a detergent. The powder particles adhere to a fingerprint as does a fingerprint powder. The gray, shiny prints that are developed with SPR can be lifted (after drying) with Gellifters, Instant Lifters or tape.
Powder suspension can be sprayed, but small articles can also be submerged in it (after diluting the ready-to-use B-86000). The SPR method has the advantage that it can be used on wet and/or dirty/greasy surfaces.
SPR White is a suspension of white powder in water with a detergent. It
works similar as the "gray" SPR (see above) but provides better contrast
on dark surfaces.
Background staining is more pronounced with white SPR. Rinsing with water after application of white SPR is therefore advised.
SPR UV is a suspension of light coloured UV fluorescent pigment in water with a detergent. It is used in the same way as the black and white version but a light source emitting long wave UV light (365 nm) is needed to view the developed marks in fluorescence.
SPR UV may provide better contrasting marks on multi coloured surfaces.