What are Release Agents

A release agent is a chemical, typically a liquid, used to facilitate the easy removal of molded or cast parts from the molds. These chemicals are applied to the contact surfaces of the mold prior to casting or molding  preventing excessive adhesion between it and the finished part. This effect is achieved by forming a second surface or a barrier layer between the mold surface and the part, which is then later removed from the finished product. These agents are typically based on silicone, oils or soapy surfactants with several special food-grade formulations utilized in the food processing industry. Release agents are widely used in a variety of applications, which include concrete casting, plastic molding, fiberglass molding and paper making.

Release agents may be liquid solutions applied with a spray gun or paint brush, wax compounds applied with a cloth or convenient aerosol types. The active components in low-viscosity liquid release agents are typically suspended in various solvents, some of which could pose health or environmental hazards. This should be kept in mind when working with or disposing of these products. In addition, as with all solvents, the maintenance of adequate ventilation and fire prevention should also be considered

Although release agents make removing molded and cast parts easy, they often have a significant effect on the surface texture of the finished product and may prevent the application of post-production finishes such as dyes and paint. The correct choice of release agent is, thus, fairly important if reject rates are to be kept at a minimum. This choice is fairly easy to make considering the extensive range of agents available. The fact that the product is often subject to considerable release agent contamination should also be kept in mind where sensitive parts meant for the pharmaceutical or food industries are being produced.

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