Non-Porous Substrate
Definition
A surface (glass, gloss metal, polished plastic) that does not absorb latent print residue, retaining it on the surface and making it accessible to powder development.
- Examples
- Glass, gloss-painted metal, polished plastic
- Residue behaviour
- Stays on the surface rather than being absorbed
- Standard development method
- Powder dusting
- Contrast
- Porous surfaces absorb residue and need chemical development instead
Common questions
Why does powder work well on non-porous surfaces but not on paper?+
Because the print residue sits entirely on top of a non-porous surface, fine powder can adhere directly to the fatty and aqueous components, whereas on a porous surface the residue soaks in within minutes and needs a chemical reagent like ninhydrin or DFO to reach it.
Does the choice of powder still matter once the substrate is non-porous?+
Yes, colour and particle size are chosen for contrast against the specific surface and lighting, and factors like surface texture, age of the print, and contamination still affect how well the powder develops ridge detail.
Related terms
- 1:1 Photography
- Macro photography at a reproduction ratio of 1:1, meaning the image on the camera sensor is the same physical size as the...
- Bichromatic Powder
- A two-component powder mixture containing both black and white particles that produce visible contrast on substrates of mixed or uncertain reflectance.
- Eccrine Residue
- The water-based secretion from eccrine glands in friction-ridge skin, containing water, amino acids, salts, urea, and lactic acid; the primary component of...
- Gel Lifter
- A tacky gelatin sheet used to transfer developed fingerprint impressions from textured or three-dimensional surfaces where conventional adhesive tape would not conform;...
- Hinge Lifter
- A pre-assembled lifting unit in which a clear acetate film hinged to a backing card is folded over a developed print, pressed,...
- Magnetic Powder
- An iron-oxide-based latent print development powder applied with a magnetic wand rather than a brush, making near-zero contact with the substrate surface...
- Magnetic Wand
- A stylus containing a retractable internal magnet that draws magnetic powder into a cluster at the tip for application to surfaces; retraction...
- Porous Substrate
- A surface (paper, uncoated cardboard, raw wood) that absorbs the aqueous component of latent print residue into its matrix, making powder development...
- Sebaceous Residue
- The oily secretion from sebaceous glands, containing triglycerides, fatty acids, squalene, and waxes, that makes up an increasing proportion of aged latent...