ABSTRACT
This chapter discusses the manufacture of the pressure-sensitive adhesive (PSA) and of the PSA-coated web, its conversion to a web-like laminate, and conversion of Pressure-sensitive products. PSA manufacture is the formulation of adhesive raw materials synthesized off-line. Solvent-based PSAs are tackified elastomers, tackified or untackified viscoleastomers, or tackified plastomers. Started with rubber-resin PSA solutions, label coating uses mostly acrylic, water-based PSAs. The formulation technology of water-based PSAs is a mixing technology of liquids, with the exception of some special formulations in which molten resins are mixed with the water-based viscoelastomer dispersion, or redispersible formulating components are used. The manufacture of hot-melt PSAs (HMPSAs) requires mechanical size reduction, micronization of certain elastomers, and molten state mixing of them with other components of the recipe. Contactless coating methods for HMPSAs were developed to allow the use of hot-spray technology for the nonwoven market. Paper, certain metals, and plastics are sufficiently polar to bond with PSAs.
