Flash-drying and flash-curing processes and equipment and radiation-curable products suitable for this purpose

摘要

A process is required to dry and harden varnishes, paints, adhesives and plastic layers which can be hardened by radiation and which contain a majority of photoinitiators covering, in combination, the range of UV-B to the range of spectrum adjacent to UV-A, where the radiation source is a high-energy electron flash device whose radiation is adapted to the sensitivity range of the photoinitiators and whose emission in the UV-C range is negligible. Preferably, the radiation-resistant mixtures contain at least three photoinitiators and cover an absorption range,Up to about 500 nm.$A Depending on the choice of the photoinitiators and their concentration, the hardening can be applied to successive lightning discharges from the surface down respectively. in the opposite direction. Preferably, the electron flash device produces a lighting intensity of 10 to 80 megalux per flash discharge.$A The procedure is suitable for a wide range of applications, e.g. for liquid and thick layers, pigmented mixtures, Protective coatings on optical surfaces as well as scratch-resistant anti-adhesive coatings, hardening of which takes place practically without thermal stress on the coated material.