The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 01, 1985
Filed:
May. 29, 1984
Robert T Foister, Rochester, MI (US);
Richard K Gray, Warren, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
A method has been developed to use a structural epoxy adhesive to bond together surfaces of phosphated steel electrodeposited with an organic primer. The specially formulated epoxy adhesive contains a cross-linkable epoxy novolac resin, an epoxy reactive diluent, and an imidazole curing agent substituted in at least one position with an alkyl or a hydroxyalkyl group. The amount of the curing agent used in the formulation is much lower than that in a conventional two-part epoxy adhesive such that the adhesive will not attack or degrade the primer layer to weaken the bond strength. The reactive diluent used reduces the viscosity of the mixed adhesive system to facilitate dispersion and wetting of the adhesive on the coated steel surface. Bond strength achieved by this method is adequate for automotive structural applications and is capable of withstanding extended exposure to humidity, salt spray, and other hostile automotive environments without appreciable loss.