We have porcelain tile floors in our home. The painters used masking tape to tape drop cloths so that they wouldn't get paint on the tile. We didn't notice anything until the cloths were pulled up and the tile was walked on for a while. Now the tape residue is on the tile and when it gets dirty, you see where the tape was. I have tried everything under the sun to get it up with no results. Can anyone help me with this problem?