Dry-erase boards, also referred to as whiteboards, have been manufactured commercially for many years. Dry-erase surfaces provide a writing surface with a non-porous character that prevents the penetration of dry-erase marker ink through the surface. Conventional dry-erase marker ink formulation includes a hydrophobic, oily release agent that inhibits permanent marking or staining of the whiteboard. The non-porous nature of the whiteboard combined with the oily, quick drying maker ink in dry erase markers allows the marker ink to be easily removed from the whiteboard.
To manufacture a whiteboard, the manufacturer coats a dry-erase coating composition onto a substrate, and allows the substrate to dry. A number of dry-erase coating compositions are known. Traditional dry-erase coating compositions are created using two components, which must be mixed together immediately prior to coating the composition onto the substrate. Such coatings are referred to as “2K” coating compositions. Many dry-erase coating compositions are formulated using organic solvents, which impart a high level of volatile organic compounds (“VOCs”), such as ethylene glycol, formaldehyde, or benzene, many of which are hazardous. In addition, the cure time for these coating compositions can be several days. In light of these attributes, such 2K dry-erase coating compositions are intended only for professional commercial application. In addition, some known dry-erase coating compositions included isocyanate compounds or epoxies. Isocyanates are hazardous, and epoxies are prone to yellowing over time.
It would be desirable to provide a dry-erase coating composition that is suitable for consumer application. For example, a homeowner, school, or office manager might wish to coat an interior wall surface with a such a coating composition to thereby create a dry-erase “wall,” or portion of a wall surface. Ideally, such a dry-erase coating composition would have a low VOC concentration (less than 150 grams/liter), and would be a single-component (or “1K”) composition that did not require pre-mixing by the consumer. The coating composition ideally would be suitable for interior architectural surfaces such as wood, drywall, cement, metal, and plaster, or over a primer coating. The dry-erase coating composition should cure at ambient temperature and without ancillary equipment such as ultraviolet lights. Upon curing, the coating composition should form a smooth, hard dry-erase coating that is resistant to interior moisture and humidity, and that is compatible with conventional dry-erase markers.
USPTO Backgrounds
USPTO Backgrounds