Cold Box Mold Release Agents
Mold Release Agent composition to facilitate separation of patterns and core boxes from foundry molds and cores .Many industrial operations require the use of release agents to reduce the tendency of a molded product to stick to the mold, or that of a tool, die or machine part to stick to the work piece.
In foundry operations, metal parts are frequently made using “sand casting” methods wherein disposable foundry shapes, such as molds and cores, are fabricated with a mixture of sand and an organic or inorganic binder, sometimes referred to as a “foundry mix”. Molds and cores are produced by chemical or heat hardening of the mixture of sand and binder onto a pattern or core box. Sometimes a catalyst is used to cure the foundry mix more rapidly. A Mold Release Agent is used to reduce or eliminate adhesion of a mold to a pattern or core box surface.
In the cold box method, a volatile curing catalyst (gaseous reagent) is passed through a shaped mixture of the foundry mix, usually in a core box, as opposed to a freestanding pattern mold. In this particular method of manufacture, the foundry mix must have adequate shelf life, meaning that it will not harden in the absence of a catalyst. The cure rate must be very rapid once the foundry mix is exposed to a catalyst.
Mold Release Agent agents are typically sprayed or brushed onto a pattern or core box surface periodically during pattern or core preparation. The Mold Release Agent can be an emulsion or dispersion. If dispersed in a solvent, the solvent serves to wet the surface of a shape-determining mold, onto which the release agent is applied. It is highly desirable to reuse the same pattern or core box many times, to generate a number of molds from the same pattern or core box. Therefore, it is important for the pattern or core to be quickly and cleanly released from the finished molds with a minimum amount of release agent residue or build up on the pattern, and with minimal need to clean the pattern surface.