[yoo-ree-uh-fawr-mal-duh-hahyd, -fer-, yoo
r-ee-uh-] 
| any of a group of resins formed by the interaction of urea and formaldehyde under conditions that include heat and pH control: used chiefly in the manufacture of buttons, baking enamels, and for making fabrics wrinkle-resistant. |
| u·re·a-for·mal·de·hyde resin (yŏŏ-rē'ə-fôr-māl'də-hīd') n. Any of various thermosetting resins made by combining urea and formaldehyde and widely used to make molded household and industrial objects. |
urea-formaldehyde resin
any of a class of substances belonging to the family of organic polymers, prepared by heating urea and formaldehyde in the presence of mild alkalies, such as pyridine or ammonia. The urea and formaldehyde undergo a condensation reaction in which they combine to form a water-soluble polymer. This polymer is used to formulate adhesives and coating agents or is mixed with wood fibre, pigments, and other substances to produce powders that can be molded into solid objects. Under the influence of heat and pressure, further reactions occur that can convert the polymer into a moisture- and heat-resistant resin. The molecular structure of the final product is that of a three-dimensional network resembling those of resins made by the reaction of formaldehyde with phenol or with melamine.
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