Radiation curable adhesives
AssigneeMerck Patent GmbH
InventorsManfred Urban, Jorg Ohngemach
Life of this patent
Estimating the term…
Abstract
Radiation curable adhesives which are based on ionically polymerizable epoxide systems and ionic photoinitiators of the triarylsulfonium complex salt type additionally also contain at least one ethylenically unsaturated substance which can be polymerized by free radicals and at least one free radical photoinitiator. These exhibit particular advantages in the gluing of optical glass components. The gluing can be partially hardened with UV radiation until fixing of the glass components is achieved. In this partially hardened state, the components can be adjusted. Complete hardening is then carried out with UV radiation.
Claims16
A method of gluing optical glass components comprising inserting an adhering effective amount of a radiation curable adhesive between the components,
- the adhesive comprising effective amounts of an ionically photopolymerizable epoxide system and an ionic photoinitiator for the epoxide system and effective amounts of an ethylenically unsaturated compound which is photopolymerizable by free radicals and a free radical photoinitiator for the unsaturated compound,
- exposing the adhesive to actinic radiation for a time sufficient for the adhesive to partially harden, but not fully harden, to an extent whereby the components are fixed to each other but remain displaceable with respect to one another, adjusting the components to achieve the desired orientation relative to one another, and then fully hardening the adhesive by exposing it to further actinic radiation for a sufficient time period.
In an optical component comprising at least two optical glass elements glued together by a radiation cured adhesive, the improvement wherein the adhesive comprises amounts of an ionically photopolymerizable epoxide system and an ionic photoinitiator for the epoxide system and amounts of an ethylenically unsaturated compound which is photopolymerizable by free radicals and a free radical photoinitiator for the unsaturated compound, wherein said amounts are effective to adhere said glass elements together.
Dependencies are inferred from the claim text.