Persistent lipsticks and their lip prints: new hidden evidence at the crime scene.

Latent lip print test results produced by permanent lipsticks are presented in this work. This cosmetic product, contrary to conventional lipsticks, does not leave visible prints and can thus be overlooked at the crime scene. As print vehicles the study used ceramics, glass, cotton fabric and paper. Lip prints were left to dwell for different periods and were later developed using aluminum powder, cobalt oxide powder and magnetic powder. The results show that identifiable lip prints can be obtained up to 30 days after being produced.