Hard, abrasion resistant coatings are used over a variety of substrates, including cement, wood, and porous substrates. Particularly demanding substrates include horizontal substrates such as sidewalks, floor tiles, cement garage floors and decks. Unfortunately, many of the commercially available coatings in use today for these substrates suffer from problems such as poor adhesion, or poor water resistance (e.g., “blushing”).
Cement and fiber cement substrates have an additional issue, in that they typically require hard, abrasion resistant coatings with excellent adhesion. In the past, this has been addressed by using higher-Tg polymer systems. Unfortunately, volatile organic content (VOC) solvents generally must be used to achieve proper coalescence of higher-Tg polymers. Consequently, there is an unmet need to develop acceptable low VOC aqueous based coatings that are hard, blush resistant, abrasion resistant and offer excellent adhesion to cement and fiber cement substrates.
Some coatings also adhere poorly near edges and corners of cement and fiber cement substrates. The applied coating may initially appear to be properly adhered but may later delaminate or otherwise prematurely fail.
USPTO Backgrounds
USPTO Backgrounds