Signal Red Polyurethane Pigment

The pigment is made up of mainly pigment powder with a small amount of the polyol Part A which means when adding the pigment, you should always add it to part A, to avoid any reaction occurring.

Due to the fact that only a very small amount of the weight of the pigment is resin (Part A), and pigment pastes are only added at low percentages themselves, it is generally not necessary to adjust the mix ratio of the resin when adding a pigment and so you should mix - for example: (100g resin part A + 5g pigment) with (100g resin part B).

The quantity of resin used in the pigment dispersions is very small and as such when the pigment is mixed into another resin, the additional amount of resin from the pigment is very small and in practical terms insignificant. As such you do not normally need to account for it within the mixing ratio calculations.

No, unfortunately you cannot use a pigment from one resin type with another resin type. You must use the correct pigment for the resin type you are using - eg a PU resin needs a PU pigment, a polyester resin needs a Polyester pigment and an epoxy resin needs an epoxy pigment.

This is because the pigment dispersions are a blend of pigment powders AND a small amount of base resin. Mixing the wrong pigment with a resin system may inhibit the resin cure and damage the end product

Yes, you can use the pigments in a resin infusion process, however if you are not using a gelcoat you will still get the colour from the fibre showing where it contacts the surface, with glass fabric the effect is diminished as the fibre is clear, but with densely coloured fibre like carbon it may affect the pigment. 

If you need a very solid colour for epoxy infusion I would advise using Polyester Pigment in the GC50 Epoxy Compatible Gelcoat.

When using a pigment paste, it is best practice to mix the paste into the resin part of the mixture. We recommend doing this before adding the catalyst/hardener as it means you have as much time as you need to get a good even colour mixture without having to worry about reduced pot life.

The pigments used in this pigment dispersion will be excellent in terms of light fastness and weathering characteristics. If you are not already aware, pigments are graded for these properties on a blue wool scale, with 7-8 being the best. We tend to only source such grades for our dispersions with such high quality. However, the base resin system you are using these pigments with may be vulnerable to UV yellowing itself.