Organic pigments are used wherever bright, strong colour is needed in a binder or polymer. The largest uses are printing inks, paints and coatings, and plastics, followed by textile printing, rubber and some specialty products.
Each use puts different demands on the pigment. A grade made for offset ink can fail in a plastic, and a plastics grade can be the wrong choice for a water-based paint. That is why you should always buy by end use, not only by Colour Index name.
Printing inks
Printing inks are the largest single use for many organic pigments. Offset, gravure and flexographic inks for packaging, publications and labels all need strong colour at low film thickness. The process colours are often built on a yellow such as a diarylide, a magenta such as a lake red, and Pigment Blue 15:3 as cyan.
Ink makers care about strength, gloss, transparency, flow and how easily the pigment disperses. Many ink grades are surface treated with resins to help wetting in a given vehicle. For food packaging they also ask about migration and impurities.
Paints and coatings
Decorative paints, industrial coatings and automotive finishes use organic pigments for bright colours that inorganic pigments cannot give. Outdoor uses need high light and weather fastness. That is where high-performance pigments such as quinacridones, perylenes, diketopyrrolopyrroles and phthalocyanines are used.
Paint makers test for flocculation, rub-out, hiding power and resistance to solvents. A pigment that is cheap per kilogram can still cost more in use if it needs a lot of dispersant or milling time.
Plastics and other uses
- Plastics makers use organic pigments in masterbatch and compounds for polyolefins, PVC, polystyrene and engineering polymers, where heat stability and migration resistance matter most. See heat stability in pigments for plastics.
- Textile printers use pigment dispersions with a binder, which avoids the wet processing that dyes need.
- Rubber, artists' colours, crayons, stationery and seed coatings also use organic pigments in smaller volumes.
- Cosmetics and food contact uses need special grades with tight impurity limits and the right regulatory documents.
How to brief a supplier
Tell the supplier your end use, your system and your process conditions. For ink, give the vehicle and printing process. For paint, give the resin and whether it is water or solvent based. For plastics, give the polymer and the highest processing temperature. Ask for a grade recommendation and a sample, then test it beside your current pigment at the same loading and under the same conditions. Read what the difference between dyes and pigments is if you buy both.
Next step
Gujarat makes a wide range of azo and phthalocyanine pigments. We find makers whose grades fit your end use, check samples in your system and have lots tested. To begin, book a free sourcing review.