Urea-formaldehyde



Urea-formaldehyde, also known as urea-methanal, is a transparent thermosetting resin or plastic, made from urea and formaldehyde heated in the presence of a mild base such as ammonia or pyridine. These resins are used in adhesives, finishes, and molded objects. Urea-formaldehyde resin's attributes include high tensile strength, flexural modulus and heat distortion temperature, low water absorption, mould, high surface hardness, elongation at break, and volume resistance.

Urea formaldehyde was commonly used when producing electrical appliances casing i.e. desk lamps. It is now mostly replaced by melamine resin.. Urea-formaldehyde foam insulation started being used in the 1950s. In the 1980s, concerns began to develop about the toxic formaldehyde vapor emitted in the curing process, as well as from the breakdown of old foam. Consequently, its use was discontinued.