How Formulation and Coating Method Impact UV HMPSAs
Understanding how tackification and coating method impact the effectiveness of UV curing helps to ensure that UV HMPSA properties are properly balanced for their intended end-use application.
Commonly used in label, non-PVC graphic and specialty tape applications, UV-curable acrylic, hot-melt pressure-sensitive adhesives (UV HMPSAs) are gaining popularity due to their quick curing properties, excellent adhesion, and versatility. In particular, many converters are switching from solvent-based rubber, solvent-based acrylic, and rubber-based HMPSAs to UV HMPSAs because they offer high durability on par with most solvent-based rubber, solvent-based acrylic adhesives and overcome limitations found in rubber-based hot-melt adhesives while also keeping environmental impact to a minimum. However, curing process challenges exist with UV HMPSAs, in particular with how the formulation and coating method (direct or transfer) can impact peel, loop tack, shear, and Williams Plasticity (WP). In this paper, we will explore how tackification and coating method impact the effectiveness of UV curing with H-Bulb. Understanding how these key variables influence performance helps to ensure that UV HMPSA properties are properly balanced for their intended end-use application.
(To note: In this article, “base” refers to an unformulated UV HMPSA, and “tackified” means base with the addition of tackifier.)