Repairing paint scratces

I am in the process of repairing about 5 light paint scratches from a vehicle not out of the way of the garage door. I have sanded it down to plasict bumper. Is it absolutely necessary to use a primer before the paint & clear coat? I would think that several coats of the paint & clear coat would be fine. Any thoughts. Thanks foryour help…

Primer or surfacer/sealer is required to provide the proper tooth for the paint to adhere.

Without it, the paint will eventually peel off the material it was applied to.

Tester

I agree with tester.

I agree too. Prep the surface just before you prime it to make sure it is clean an most receptive to paint.

You probably need a primer made for urethane bumpers.