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moldmakingtechnology.com 33 Images courtesy of Chem-Trend. improve process efficiency, as well as the necessity to meet environment and workplace requirements. Eliminating solvents from a release agent, while good for the environment and shopfloor workers, presents a unique set of challenges to chemists. Water-based carriers have been traditionally thought of as unreliable because of their instability, suscepti- bility to bacteria growth and predisposition to freez- ing in low temperatures. In addition to helping the part slip easily from the mold once it has been molded, release agents must first provide a dry molding surface onto which the polyurethane is applied. If the surface is wet, any number of nega- tive results can occur, from inconsistent surface quality to blemishes on the fin- ished part. For example, many integral-skin applications must meet gloss and color-matching requirements. In the absence of post-mold cosmetic processes, the mold release agent is often relied upon to provide the required part appearance. Therefore, only the highest-performing release agents that help manufacturers achieve flawless and harmonious surfaces should be acceptable, regardless of the polyurethane's com- position (water or solvent). Creating a solvent-free release agent that quickly and eas- ily releases a molded part, but leaves a consistent, dry film on the mold's surface is the challenge for chemists. They understand that a dry mold surface is the key to molding parts with the desired cosmetic appearance in any industry, from automotive to furniture to the manufacture of shoe soles. Without the ability to provide the same release proper- ties, surface quality and post-molding processes, water-based solvents are useless to manufacturers. One new release technology eliminates the difficulties related to previous water-based release agents and forms a dry release film before the polyurethane is poured. Another These integral-skin steering wheels show the various gloss levels that are attainable with water-based release agents. A water-based agent was used to release this polyurethane foor mat without problems.