You may need to remove old glue, chewing gum or sticky tape from a porcelain or ceramic floor. This must be done very carefully with specialist products to avoid damaging the surface.
Apply PS87 PRO (diluted approx. 1:3 on surfaces previously dampened with water), and rub energetically with an abrasive green sponge.
To remove surface residue, you can also use ZERO SIL*: apply the undiluted product over the entire stain, leave it to act for 20 minutes, then scrape it off with the spatula included in the kit. You can then pick up the residue with paper towel or a cloth. Rinse abundantly.
*check product availability in your market