Ensuring Successful Adhesion of UV-Curable Coatings to Plastic Substrates
The reasons for the growth of the UV-cure coatings market include not only performance improvements, but environmental issues and increased processing efficiency. UV curing of coatings does not create excessive heat generation and overcomes many of the shortcomings of thermal curing, particularly where plastic substrates are concerned. UV curing is the most efficient, environmentally clean and low-energy method for coating plastics. Also, the variety of acrylate and methacrylate monomers and oligomers used in UV-curable coatings provides coating formulators with unlimited options, enabling them to achieve specific, desired coating properties.
Regardless of the cure method, ensuring strong adhesion of coatings to plastic substrates can be a challenge. Plastics are typically nonporous substrates and adhesion to these surfaces is often difficult to achieve. Unlike metal substrates, where a chemical as well as a physical bond can occur, plastic substrates have only a physical bond present.