1. Introduction
Fingerprints have often been and still are considered one of the valuable types of physical evidence in identification. In general, three forms of fingerprint evidence that may be found at a crime scene are visible (or patent) prints, impression (or plastic) prints and latent prints. Latent prints are not visible to the naked eye and thus require some means of development or enhancement for their visualization. New techniques have been developed for latent fingerprint detection but the traditional fingerprint detection technique for treating latent prints is powdering method. When the fingerprint powder is sprinkled over an affected area, the powder adheres to the oil, sweat or other materials left in a fingerprint. Powdering technique has been used as a technique since the early 1900s. Over this period, many fingerprint powder formulations have been in use, with each formula consisting of a colorant for contrast
and a resinous material for good adhesion.1 Hundreds of fingerprint
powder formulas have been developed over the years.
In general, there are four classes of fingerprint powders-regular,
luminescent, metallic and thermoplastic.2
In the past, powder dusting, ninhydrin dipping, iodine fuming
and silver nitrate soaking were the most commonly used
techniques for latent print development. These traditional
techniques are quite effective for many surfaces. However,
these traditional methods for latent print detection are not always
effective and scientists have attempted to improve the
existing methods for the visualization of latent prints. There
are different powders which have been used by various