Effect Pigment
Definition
Aluminium flake or TiO2-coated mica used in metallic and pearlescent automotive finishes; identified by SEM morphology and EDS elemental composition.
- Materials
- Aluminium flake, TiO2-coated mica
- Finish types
- Metallic and pearlescent automotive finishes
- Identification method
- SEM morphology plus EDS elemental composition
Common questions
Why does an effect pigment need both morphology and elemental analysis to identify?+
Aluminium flake and mica particles can look broadly similar under low magnification, so SEM imaging of particle shape and size distribution is combined with EDS elemental data, distinguishing metallic aluminium flakes from TiO2-coated mica by composition as well as appearance.
Why are effect pigments useful for discriminating between paint samples of similar colour?+
Two paints can match closely in visible colour under standard lighting yet contain different flake size, shape, or orientation, which affects how the paint sparkles or shifts colour with viewing angle, giving an additional comparison point beyond bulk colour matching.
Related terms
- Alkyd Resin
- A polyester binder modified with fatty-acid chains from drying oils; cures by oxidative crosslinking and is characterised by FTIR ester carbonyl absorption...
- Basecoat
- The colour-bearing layer in automotive OEM paint; thin (10-30 µm), thermoplastic acrylic binder, contains colour and effect pigments.
- Binder
- The polymer matrix that holds pigments in place and bonds the paint to the substrate. Identifies paint type (alkyd, acrylic, polyurethane, epoxy)...
- Clearcoat
- The transparent outermost layer of automotive OEM paint; thermoset acrylic-melamine, 40-60 µm, provides UV resistance and gloss.
- Electrocoat (E-Coat)
- The first layer in automotive OEM paint, applied by cathodic electrodeposition of an epoxy-amine coating onto the bare steel shell; 15-25 micrometres...
- ENFSI EPG
- Expert Working Group on Paint (European Network of Forensic Science Institutes); produced the European paint-examination protocol and promoted EUCAP development.
- PDQ
- Paint Data Query database (RCMP-maintained). Cross-referenced from glass work when a vehicle is identified through paired glass and paint evidence.
- Phthalocyanine
- Highly stable organic pigment providing intense blue (PB15, copper phthalocyanine) and green (PG7) colours; identified by Raman bands at 680 and 748...
- Refinish Paint
- Paint applied in body-shop repair; typically 2K polyurethane, chemically distinct from OEM acrylic-melamine; adds extra layers visible in cross-section.
- SWGMAT
- Scientific Working Group for Materials Analysis, a US forensic science standards body (now succeeded by the OSAC Explosives Subcommittee). Published the Forensic...
- TiO2 Polymorph
- Titanium dioxide exists as rutile (Raman 143, 447, 612 cm-1) or anatase (Raman 144, 197, 399, 513 cm-1); the polymorph distinguishes premium...