Wood Processing With Impregnation Resin
Impregnation is a process whereby natural materials such as wood, concrete or other hard substances are combined with an inert additive to yield a smooth, dense product. Impregnation is a relatively new process, introduced to the woodworking industry in the 1970s by a few manufacturers in New Zealand. Since then, it has become one of the most popular woodworking processes and is being used worldwide in wood processing and finishing.
Impregnation is a process where a wood impregnating agent is mixed with a medium that provides solidification properties. Imparting impregnation resins into a finished wood substrate during wood processing, impregnation resins become polymer-like substances to cure within a wood substrate. When mixed with a penetrating wood filler, the impregnant resin is further polymerized, becoming a hard material with fine grain, excellent toughness, high tensile strength and wear resistance. The resin impregnating agent used for impregnation can be chosen from many sources. The most common pregnant agents are resins of natural minerals such as copper oxide, and wood resins such as oak, maple, cherry, birch, beech, walnut and ebony.
Impregnation resin and wood processing are closely related but are not identical. Wood processing uses mechanical or chemical processes to soften or straighten wood. Impregnating resins and wood processing are two completely different techniques. Imputting resins into a finished hard wood substrate involves a process that removes all impurities from the wood surface, leaving a clean and polished wood surface with a uniform grain, color and texture.
Impregnant resin used for wood processing is a clear, odorless substance that easily penetrates the wood and leaves a fine, uniform, clean finish. It is usually mixed with water and allowed to dry for approximately seven hours before it is added to a wooden substrate. A water based impregnant filler is typically mixed with a water-based polyurethane to increase its density and prevent the wood from absorbing the filler. Once the wood has dried for a sufficient length of time to allow for impregnation, the impregnant filler is cured in a kiln for approximately thirty days at between treatments.
Wood impregnation imparts a smooth, hard, dense wood surface that is hard wearing and can resist high levels of wear. Because of its unique properties, pregnant resin impregnates the surface of finished wood products such as furniture tops, flooring, cabinet doors, floor boards, doors and door and trim, window sills, doors and lintels, and skirting board, door and window sashes, paneling, floor boards, floor joists and ceiling panels and lintels. If pregnant resins are not applied correctly, they will leave a smooth, shiny finish but uneven surface. Therefore, proper pregnant application is essential in achieving the best results.
The popularity of impregnation is increasing across the world as wood processing equipment becomes more affordable, easy to use, reliable and effective. Wood impregnation has been used as an important part of the woodworking industry for many years, but impregnation has only recently come into prominence because of the ease of use of wood processing equipment. There are many benefits to impregnating wood products such as the durability, strength and affordability of wood products.