PURPOSE: A thermosetting adhesive having excellent heat resistance and peeling strength and being particularly suitable for MCL, comprising a polyfunctional epoxy compound, a Schiff base bond-carrying amine type compound and a polyvinyl acetal.

CONSTITUTION: Titled adhesive is obtained by dissolving, in a solvent such as acetone, (i) a polyfunctional epoxy compound such as a glycidyl ether of bisphenol A, (ii) a Shiff base bond-carrying amine type compound represented by the formula, wherein R1W2 are each an atomic group of 2C or higher and (iii) a polyvinyl acetal such as polyvinyl formal. Compound (ii) is prepared by reacting a hydroxyaldehyde compound such as 2-hydroxyisophthalaldehyde with an amine type compound such as m-phenylenediamine in a solvent such as methanol. Component (iii) is used preferably in an amount of 1W60pts.wt./100pts.wt. of the sum of components (i) and (ii).