Energy-curable

As pointed out above, radiation or energy curable adhesives can be essentially hot melts or liquids at the room temperature. For this technology, a liquid curable PSA formulation is comprised of four essential components ... 

Energy curable adhesives for use in flexible packaging based on ultraviolet or electron beam irradiation are in their infancy. The potential use of these types of adhesive is promising due to the fast cure rate (essentially full cure on irradiation and hence low risk of migratory components) and the potentially... 

In approaching the development of an energy-curable resin system, we have attempted to solve a number of problems with which the ultimate user of these types of materials is faced, namely ... 

Oxygen inhibition of cure which exists in many energy-curable resins necessitating the use of inert blanketing. 

Much has already been published concerning the composition of energy-curable resin systems for use In coatings and Inks, and the basic approach to the development of such vehicles Is well known (Refs. 1, 2, 3). A typical formulation contains an oligomer, which may or may not contain reactive functional groups (e.g., double bonds), a cross-linking agent, a reactive diluent (for viscosity control), and a photosensitizer or photolnltlator. 

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... 

The Uvimers comprise a useful new group of energy-curable resins suitable for a wide variety of applications. Special features which should be of interest to potential users include ... 

Uses Defoamer in inks and coalings, solventless, solv., waterborne, and energy-curable systems, food-contact inks and coatings defoamer in food-confact paper coatings, paper/paperboard food pkg. adhesives Regulatory FDA21CFR 175.105,175.300,176.170,176.180,176.200, 176.210... 

NZ 97 Stmktol PEH-100 PL release agent, energy-curable pigmented systems... 

This overview of radiant energy curable technologies for adhesives includes discussions of the form of radiant energies, where they are used, their market size, chemical nature, and properties. The article centers on ultraviolet, infrared, and electron beam technologies. 

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