I don’t know what’s getting into your paint. Dust could be a function of painting in a dusty environment or even lint from paper towels or rags you use to clean brushes with while painting. You might want to try varying your procedures, such as slightly different materials or working in a different room, to try to narrow down exactly what the problem is. Note that vacuuming makes the air in a room more dusty for several hours until it settles. Ionizing dust filters, if you use one, work by giving surfaces a small electric charge that dust is attracted to, so they actually cause more dust to attach itself to paintings.

What is the medium you are mixing the Liquin with? Some materials, such as stand oil, seem to attract dust. I personally don’t use alkyd mediums such as Liquin, so I don’t have any experience with whether it attracts dust. One option if dust is falling on your painting while it dries, however, is to hang it at an angle outward (with string and thumb tacks, for example). You could also put a cloth over it, arranged so that the cloth doesn’t come into contact with wet paint.

Best wishes,

David