Multi-layer, heat-curable adhesive film
AssigneeCiba-Geigy Corporation
InventorsKarl Urech, Roland Moser
Life of this patent
Estimating the term…
Abstract
Multi-layer, heat-curable adhesive film having a tacky external curable layer A and a dry external curable layer B, containing various adducts which contain epoxide groups and are formed from an aromatic diglycidyl or polyglycidyl ether together with a carboxyl-terminated butadiene/acrylonitrile rubber and adducts of this type with a carboxyl-terminated polyester, and also aromatic diglycidyl or polyglycidyl ethers, varying amounts of fillers, dicyandiamide as a curing agent, a curing accelerator and, if appropriate, a carrier material between the layers A and B, is suitable for bonding various substrates and is preferably employed for bonding metal structural components without prior cleaning of these components.
Claims10
A multi-layer, heat-curable adhesive film having a tacky external curable layer A, containing
- (a) 15 to 40% by weight of an adduct I containing epoxide groups and formed from an aromatic diglycidyl or polyglycidyl ether having an epoxide content of 3.5 to 6.5 equivalents/kg and a carboxyl-terminated butadiene/acrylonitrile rubber or a carboxyl-terminated polyester,
- (b) 15 to 40% by weight of an adduct II containing epoxide groups and formed from an aromatic diglycidyl ether having an epoxide content of 0.3 to 3.0 equivalents/kg and a carboxyl-terminated butadiene/acrylonitrile rubber or a carboxyl-terminated polyester,
- (c) 16 to 30% by weight of an aromatic diglycidyl or polyglycidyl ether having an epoxide content of 3.5 to 6.5 equivalents/kg,
- (d) 0 to 6% by weight of an aromatic diglycidyl ether having an epoxide content of 0.3 to 3.0 equivalents/kg,
- (e) 10 to 25% by weight of one or more customary fillers,
- (f) 1 to 6% by weight of dicyandiamide,
- (g) 0 to 2% by weight of a curing accelerator and,
- (h) further customary additives, the components (a) to (h) adding up to 100% by weight,
- a dry external curable layer B, containing
- (a) 15 to 40% by weight of an adduct I containing epoxide groups,
- (b) 15 to 40% by weight of an adduct II containing epoxide groups,
- (c) 0 to 15% by weight of an aromatic diglycidyl or polyglycidyl ether having an epoxide content of 3.5 to 6.5 equivalents/kg,
- (d) 0 to 6% by weight of an aromatic diglycidyl ether having an epoxide content of 0.3 to 3.0 equivalents/kg,
- (e) 15 to 40% by weight of one or more customary fillers,
- (f) 1 to 6% by weight of dicyandiamide,
- (g) 0 to 2% by weight of a curing accelerator, and,
- (h) further customary additives, the components (a) to (h) adding up to 100% by weight.
Dependencies are inferred from the claim text.