Desk loses edges after solvent goes red (7)

I believe the answer is:

flushes

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'edges after solvent goes red' is the definition.
The definition and answer can be both to do with contact as well as being verbs in their -s form.
Maybe there's an association between them I don't understand?

I don't understand how the remainder of the clue works.

Can you help me to learn more?

I've seen this clue in The Daily Express.

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