Suction cup marks on thin porcelain slabs

[Sophie77]

Last week I had seven porcelain slabs of 120 x 260 cm installed on a wall in my house. A couple of days later I started noticing dark ring marks left by the suction cups used for lifting the tiles and fitting them on the wall. The tiles are 6 mm thick, glazed, and produced by Italgraniti (see the picture for all the details about the tiles).

The tilers tried removing the marks with regular surface cleaning products but nothing worked so far. In fact, it seems like the ring marks are sitting beneath the surface rather than on top of it. Strangely, when comparing the pictures from the day of installation and now, it looks like the marks were not there right after the installation but appeared later on.

Does anyone know what might have caused the marks and, more importantly, how to remove them without damaging the tiles?
Thanks for any help!

 

[Bill]

I would like to say it is just trapped moisture and will dry out but having seen the photo, I am a tad bemused by it.

 

[Italy]

it was the black rubber of the suction cups. it will be difficult to remove, almost all tiler tool manufacturers no longer use black rubber for this reason.

 

[Old Mod]

Try Lithofin Wexa, it can be used for oil and wax removal.
I’ve had good results with this and ceramic clean with stubborn marks on thin porcelain

 

[Tile Fix Direct]

The solvent in WD40 may remove it, but try on an off cut firs to make sure you do not make matters worse!

 

[Sophie77]

Thanks everyone for your comments and suggestions. I will try both Lithofin Wexa and WD40 in the following days and hopefully one of them will solve the problem.

 

[Dan]

How did you get on with this?

 

[Mark K]

Thanks everyone for your comments and suggestions. I will try both Lithofin Wexa and WD40 in the following days and hopefully one of them will solve the problem.

Hi, did you any luck with this. I have similar thing on new porcelain patio slabs

 

[Grizzly111]

Does anyone have a solution to suction cup marks on porcelain tiles? Have tried many things including Faber Tile Cleaner, Acetone, magic sponges and various other solvents.

 

[Grizzly111]

And by the way, I have confirmed with the factory that these marks are caused by their suction cups. These things seem impossible to remove.

They have come back to me and recommended an acid cleaner first (leaving on for 20 mins and rubbing with a Magic Sponge) then using a Faber Alkaline cleaner. High-End Italian porcelain floor tiles. Open to hear anyone else's recommendations?