Yellow spots on VCT floor

[Andy12]

Hello to all , What is the best way of removing yellow spots after I strip the VCT floor?

There was a rug in that spot.
View attachment 449
Thank you for your time.

 

[Lee Stockwell]

Not usually removable. "Plasticiser migration" is the technical term. If the underlying tile is thick enough you can eventually grind enough off the surface to be acceptable.

We had to do this in a bank lobby once.