I'd try these solvents in this order:

Warm water
Isopropyl alcohol (rubbing alcohol)
Turpentine (distilled from pine tree sap)
Xylene (dimethylbenzene)
MEK (methyl ethyl ketone)
Acetone (solvent for some lacquers)

The first three are safe and I haven't found they will soften any chips. The last three are flammable and will attack the chip so use sparingly and quickly.

Don't immerse the chip in solvent, just use a cloth wet with the solvent and wipe the chip with it.

Most of these solvents can be purchased in a paint store. Check the list of ingredients to see which is which.