LATENT CURING AGENT FOR ONE-COMPONENT EPOXY RESIN

• Main Authors: TAKEUCHI KOJI, TABOHASHI KEN, HIRAI KIYOMIKI
• Format: Patent
• Language: English
• Published: 16.08.1986
• Subjects: CHEMISTRY; COMPOSITIONS BASED THEREON; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP

PURPOSE:To obtain an epoxy resin composition which is good in storage stability, low-temperature rapid curability and can give a cured product improved in transparency and water resistance, by using a specified hydrazide as a curing agent for the epoxy resin. CONSTITUTION:A latent curing agent comprising a hydrazide represented by formula I (wherein X is a residue derived by removing the two hydroxyl groups from a dihydric phenol and is a group of formula II or III). It is preferably that X in formula I is a residue derived from a dihydric phenol selected from among catechol, resorcinol and hydroquinone. The amount of the latent curing agent added is about 0.5-1.5 equivalent, in terms of equivalent of the epoxy groups in the epoxy resin. Said hydrazide compound can be readily obtained by the action of hydrazine hydrate on a diglycolate diester compound derived from 1mol of a dihydric phenol and 2mol of sodium monochloroacetate (formula IV, wherein X is the same as in formula I and R is an alkyl group).