abstract |
A powder coating compositions incorporates a wax in post-blended form, the composition incorporating the wax and the same composition without the wax being separated, preferably widely separated, in a triboelectric reference series indicative of the extent to which powder coating compositions may be distinguishable from one antoher when electrically charged. The powder coating compositions incorporating a wax in post-blended form is especially suitable for coating articles having recessed portions. A quantitative basis is given for determining separation in the triboelectric reference series, and preferred minimum separation criteria are given. The effects obtainable using post-blended wax may be enhanced by the use, as further post-blended additives, of a combination of aluminium oxide and aluminium hydroxide. |