ELECTRON FLASH DRYING AND CURING PROCESS AND DEVICES, AND RADIATION-CURABLE PRODUCTS

摘要

A process is disclosed for drying and curing radiation-curable lacquers, paints, glues and plastic layers which contain a plurality of photoinitiators which together cover a spectral range extending from the UV-B range to the visible range adjacent to the UV-A. The radiation source is a high energy electron flash generator whose radiation is adapted to the sensivity range of the photoinitiators and whose emission in the UV-C range is negligible. Advantageously, the radiation-curable mixtures contain at least three photoinitiators and cover an absorption range up to about 500 nm. According to the choice of photoinitiators and their concentration, curing may occur during successive flash discharges from the surface downwards or in the reverse direction. Preferably, the electron flash generator achieves an illuminance of 10 to 80 megalux per flash discharge. This process is suitable for a wide range of applications, for example for liquid flat coats and thick coatings, for pigmented mixtures, for protective layers on optical surfaces and scratch resistant anti-fogging layers which may be cured practically without thermally stressing the coated material.