In the 1990s, when concrete polishing took off in the United States, silicate hardener/densifiers were rarely used. Now, a concrete floor is not considered properly polished if densifier has not been applied to rejection. Using diamond abrasive tooling alone was not enough for durable polished concrete, and the use of chemistry became a must-do step.
The use of densifiers should also be expected when maintaining polished concrete floors with diamond floor pads.
After using these pads, clean the floor with a slightly alkaline cleaner and water. This will suspend the particulate that was removed during the pad process, break the surface tension and allow you to check for water absorption. If water penetrates and darkens the concrete, so will all other liquids that the floor is exposed to. When a polished concrete floor absorbs water, it is a clear sign that the concrete should be redensified. Or, a conditioner can be applied, although conditioner should not be used over guard coatings or stain protection.
Densification creates more calcium silicate at the surface, which hardens the concrete, prevents further abrasion and degradation, and makes the floor easier to clean and maintain.