What kind of heat can your epoxy resin coating handle? The answer is in its heat resistance rating and recommended service temperature.
Is epoxy resin heat resistant?
Epoxy resins are formulated differently for different purposes, and therefore will exhibit different characteristics depending on their desired performance. Industrial Clear epoxy resin is formulated to withstand high heat once cured because it is intended for use on countertops, bar tops, tables, and other surfaces meant to accommodate hot objects. If you use an epoxy resin that is not formulated for high heat resistance, the surface will soften when heat is applied and then re-harden with potential indentations, or a loss of shine. For example, you wouldn’t want coffee cup rings embedded in your table top because you used the wrong finishing coat.
In order to determine the heat resistance of an epoxy resin, the manufacturer tests for the softening point, or heat deflection point. The softening point is directly related to the hardness and brittleness of the final cure, all of which are directly affected by the chemistry used in formulation. A high temperature softening point means that the epoxy resin will maintain its smooth, high-gloss properties under high heat.
Heat Resistance vs Recommended Temperature
It should be noted that heat resistance is not the same as recommended service temperature. The heat resistance indicates the point at which cured epoxy resin can essentially be melted back into a liquid again, albeit a catalyzed liquid. For Industrial Clear, this number is 500º F or higher. This number does NOT represent the temperature the resin coating can withstand from a hot object being placed on it—instead, that is the recommended service temperature.
The recommended service temperature isn’t typically quantified the same way heat resistance is, because it’s more useful to relay the information in terms of what applications are appropriate. For example, you may not know that a hot cup of coffee clocks in at 134º F / 56º C, so it’s better to just say that the product can withstand a hot cup of coffee. For Industrial Clear, the recommended service temperature allows for hot coffee cups without leaving a mark in the surface, but not, say, a casserole dish straight out of the oven. This makes Industrial Clear an ideal resin for tables and coasters, and we do recommend it for countertops in conjunction with hot plates, as other materials such as laminate, quartz, granite, and butcher block carry the same recommendation.
As with all epoxy resins it is important to stick to the proper mixing ratio to maintain the integrity of the heat resistance rating. Industrial Clear is mixed at a 2:1 resin to hardener ratio. Measure accurately and stir thoroughly for best results. Again, with all epoxy resins and regardless of cure time, it is best to wait a full week before using a coated surface so that the final 1% of curing can take place, allowing the resin to reflect its accurate heat and hardness profile.
We hope that this information will give you the confidence to use Industrial Clear on your table, bar top or counter to create something beautiful, functional and durable.