Pigment Blue 15:3 and Pigment Green 7 are copper phthalocyanine pigments used in inks, paints, plastics and coatings. To specify them, state the C.I. name, strength against a standard, shade, dispersibility, heat stability, particle form and moisture. The same points also decide the pigment blue price per kg you are quoted.
This article does not give prices. It explains which spec values matter and what moves a quote, so you can ask suppliers for comparable offers.
What the two pigments are
Pigment Blue 15:3 is the stable beta crystal form of copper phthalocyanine, a green-shade blue that resists crystal change and flocculation. Pigment Green 7 is the same structure with chlorine atoms replacing hydrogen, giving a bluish green. Both are very durable and widely used.
Our guide on phthalocyanine pigments gives the background.
The spec values that matter
Ask for these in the specification, each with a test method and a tolerance:
- Colour strength and shade against a named standard, tested in your own vehicle, such as an ink, a paint or a plastic.
- Dispersibility: how easily the pigment breaks down and how fine the dispersion becomes. See dispersion quality in pigments.
- Heat stability at your processing temperature, which matters for plastics. See heat stability in plastics.
- Crystal form and flocculation resistance, which decide whether the colour is stable in solvent-based systems.
- Moisture, water-soluble salts and oil absorption.
- Particle form: powder, granules or a pre-dispersed paste.
What moves the price
Quotes for the same C.I. name can differ widely because the products are not identical. These factors do most of the work:
- Raw material cost, mainly copper, phthalic raw materials and, for Green 7, chlorine, together with the energy used.
- Strength: a stronger pigment lets you use less per batch, so compare cost per unit of colour, not per kilo.
- Treatment and finishing: surface treatment and milling raise dispersibility and the cost with it.
- Order size and pack: bulk bags, fibre drums or small packs cost differently per kilo.
- Freight, insurance and the Incoterm, which change the landed figure.
Because of these differences, never compare unit rates without comparing strength and dispersion in your own system.
How to get a reliable quote
Send every supplier the same specification, the same annual volume, the same pack and the same Incoterm. Ask each to quote against your standard sample, and request a sample from current production to test before you decide. Our guide on comparing chemical quotes on an equal basis shows the method.
Ask how long the quote stays valid, because input costs change. A real quote for your grade and volume comes from a sourcing review.
Which use changes the specification
The same C.I. name can need different specifications in different uses. A printing ink buyer cares most about strength, gloss and flow. A paint maker also looks at flocculation resistance and weather performance. A plastics processor cares about heat stability and dispersion in the polymer.
Say which use you buy for, and let the supplier propose the grade. Our guide on organic pigments for inks, paints and plastics covers the differences, and a supplier that cannot discuss your use is a warning sign.
How we help
We find and audit pigment makers, check samples and documents, have lots tested, and supervise production and loading. To get comparable quotes for these pigments, book a free sourcing review.