Back to results
US 6,204,309 B1Granted
Fluorescent cyanoacrylate adhesive
AssigneeHenkel Kommanditgesellschaft auf Aktien
InventorsHanns R. Misiak, Heinz C. Nicolaisen, Annette Schroeter, Dagmar Behn
Life of this patent
Estimating the term…
Abstract
Cyanoacrylate adhesive containing a pyrylium salt as a fluorescent dye are useful for bonding various substrates, particularly transparent plastics. The pyrylium salt may be present in relatively large quantities in the adhesive without any adverse effect on the storage stability and adhesive properties, yet shows very little inherent coloration in visible light.
Claims25
A method for bonding substrates which comprises:
- applying to at least one of the substrates to be bonded a layer of an adhesive comprising at least one
- α-cyanoacrylate and a pyrylium salt of the formula:
- in which R1 to R5 represent independently hydrogen, an alkyl group containing 1-18 carbon atoms, an aryl group containing 1-18 carbon atoms and an aromatic group containing up to 18 carbon atoms fused at two vicinal positions, wherein R1 to R6 may be substituted with alkyl, aryl, alkoxy, aryloxy, halogen or pseudohalogen, and A comprises a non-nucleophilic counterion, joining the substrates and irradiating the adhesive with radiation of a wavelength which causes the adhesive to fluoresce wherein the irradiating is carried out before or after the substrates are joined.
Dependencies are inferred from the claim text.