UV curing technologies

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. ... 

The main potential for expansion of UV/EB into aerospace and certain commercial applications is by developing radiation curing of polymeric fiber-reinforced composites. The initial work on composite skin repairs involve applying the UV curing technology with bisacryl phosphine oxide to ensure the cure of relatively thick layers. A total of ten layers were used at a time. The UV cured composites closely matched those produced by heating. ... 

Shukla V, Bajpai M, Singh D, Shukla R. (2004) Review of basic chemistry of UV-curing technology. Pigment Resin Technology 33(5) 272-279. 

The wide use of photoinduced radical or cationic polymerization of unsaturated monomers in UV curing technologies [1-3] have stimulated many detailed investigations of the processes involved [4-10]. Time-resolved laser-spectroscopy has been extensively employed [7 and references therein][8][11-20] to study in real time, the dynamics of the excited states of molecules used as photoinitiators. Reaction models accounting for the photoinHiation steps of the polymerization have been proposed which allow relationships between the excited state reactivity and the practical efficiency as photopolymerization initiators to be discussed thoroughiy. 

One of the unique advantages of photoinitiated polymerization lies in the rapidity of the process, which transforms within seconds a liquid resin into a solid polymer material. This UV-curing technology, which has been thoroughly investigated in the past decade, " has found a large variety of In Situ Spectroscopy of Monomer and Polymer Synthesis... 

FIGURE 3.4 Chemical grafting reaction of acrylic polymer backbone with photoreactive groups in acResins using UV curing technology... 

The use of fluorinated structures in polymeric networks is veiy attractive due to their peculiar characteristics, connected to the presence of fluorine, such as chemical and thermal stability, weathering resistance, low surface tension, hydrophobicity and oleophobicity, optical and electrical behaviour [32]. It seemed interesting to employ fluorinated structures in UV-curable systems in order to combine the properties of these molecules and the advantages of the UV-curing technology, giving rise to eured products with outstanding properties. 

UV cure technology combined with PVD processing provides an environmentally friendly means of producing flexible, bright plasticparts which satisfy consumer demands for durable god looking parts in a wider range of industries. 

UV curing technology provides and especially robust organic protective coating system. It s highly crosslinked nature yield exceptional surface hardness while providing exceptional gloss, durability and water-clear appearance. 

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