Clear oil based varnish (brush cleaned with white spirit) will not cause any harm.
Clear cellulose is an absolute NO – it causes the vinyl to shrink.
Acrylic aerosols are a grey area, it is best to do a test on the sample of vinyl we always provide for this purpose.
Graphics can be oversprayed with Two Pack (note manufacturers safety instructions), the first coat must be a light mist coat (do not add extra thinners) followed by a full coat some 30 minutes later.
We have also tried Le Tonkinois Varnish with excellent results,
Phone: 01 628 629829 or 548840 but the smallest amount they offer is a half litre tin.
Email: email@example.com for further details.
Please remember that modern fuels will attack the print and adhesive on vinyl graphics because of it’s aggressive nature, it is also now damaging paint finishes. This problem is gradually getting worse so beware, and always renew the sealer on your filler cap at regular intervals – don’t wait for it to start leaking.