Energy Curable Pressure-Sensitive Adhesives

UV curable pressure-sensitive adhesives (PSAs) are based on two types of UV curable maferials  

Maferials fhaf already are pressure-sensifive adhesives, buf can be modified by radiation (UV or EB) to infroduce or increase cross-linking, which increases their adhesive properties, shear value, peel strength, service temperature range, and solvent resistance 

Materials, such as acrylates with tackifiers, acrylate polyesters, and polyurethanes, that do not have properties as pressure-sensitive adhesives, but after cross-linking have desired pressure-sensitive properties 

Monofunctional urethane acrylate in EHA 26.1 Base resin (elastomer) 

In the past, electron beam radiation was applied to produce PSA exclusively however, recent improvements in UV curing technology (precise UV dose control, suitable photoinitiators) permit UV to be used to produce pressure-sensitive adhesives. PSA formulations can vary in consistency from low-viscosity liquids up to solids melting at 80°C (176°F). Therefore, applications may vary from screen printing to roll coating to melt extrusion. Coat weights for most PSA materials vary from 1 to 10 g/m.  

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Recently, Dowbenko et al (Ref. 4) of PPG Industries described two approaches to the development of energy-curable pressure sensitive adhesives. One Involved the incorporation of low molecular weight acrylic polymers into hot melt formulations the second employed radiation polymerization of monomer-polymer syrups. 

TABLE X - PRESSURE SENSITIVE ENERGY-CURABLE ADHESIVES... 

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