Signal Red Epoxy Pigment

Hi Anton, if you're finding the past too thick to disperse into your resin mix, it might be that you're storing or using it too cold. Like epoxy itself, our pigment pastes are fairly sensitive to temperature when it comes to their viscosity. If they're cold, they will feel particularly thick, so the first thing would be to check the temperature you're storing them at.

If this doesn't solve the problem and you are still keen to 'thin' the pigment paste for future use then yes, in theory, you could add a small amount of additional epoxy resin (resin side only) to the paste in order to dilute it slightly. However, it's important to understand that the percentage of epoxy that's already been used to disperse the pigment is very small, which is why we don't suggest you need to allow for it when calculating your hardener ratio in your resin mix. If you start to add significantly more resin to the pigment paste then you'll be getting into a territory where you do need to allow for the extra resin in the pigment.

Yes, certainly. In fact, with the range of pigments that we carry, you can mix them together to achieve just about any colour you need.

Our pigments have a stated shelf-life of 12 months however I don't think there would be any problem using a pigment that was well past this age. We wouldn't sell an old pigment but I have experience of using 3yr old pigments and encountering no problems. As with anything, storing appropriately and sealing tightly would be important.

Our West and Senior Epoxy Pigments are designed to work with all epoxy resins. However there is always the odd chance of incompatibility if the epoxy is for a unique use or formulation. So we would recommend contacting your resin manufacturer if you have any doubt, or simply conduct a small curing test before using the pigment on your main project.

These pigments are a thick liquid paste (dispersion)

The pigment ratio is based on the total weight of the resin AND hardener. However, for mixing purposes we always recommend adding the pigment to the resin part BEFORE adding the hardener to allow you plenty of time to properly mix, so that means you will just need to plan ahead slightly so you know what your total resin and hardener mix will weigh.

Yes these pigment pastes are suitable for use with the GlassCast range of resins and can be used to make a bold opaque colour.

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.