1. Solubility of certain dyes and pigments when overcoated, causing topcoat colour to be slightly tainted
  2. Excessive amounts of peroxide hardeners in polyester fillers
  3. Traces of tar-underseal can bleed when oversprayed


  1. Old colurs can be tested for bleeding by applying a light colour (white) over a small area and leaving for a few minutes. Bleeding will generally occur after a few minutes. Do not allow spray dust from bleeding colours to fall on other jobs
  2. Only use the recommended amount of peroxide hardener in polyester fillers
  3. Remove all traces of road tar and underseal during preparation


  1. The best way to rectify an area of bleeding is to totally remove the paint and then re-coat. Alternatively, the use of isolator/sealers can seal in the bleed. However, avoid thick films of the isolator/sealer
  2. Bleeds occuring from peroxide hardeners can be sealed by the application of a polyester primer surfacer