Candle wax is the primary component of a candle, functioning as the fuel source for the flame. The wax is composed of hydrocarbons, compounds made of hydrogen and carbon atoms. When the wick is lit, the heat melts the solid wax into a liquid, which is then drawn up the wick by capillary action. This liquid wax is vaporized and combusts, releasing energy as heat and light.
The specific chemical makeup of the wax determines the candle’s performance, including its burn time and the intensity of its fragrance release, known as scent throw. The choice of material directly affects the final quality and characteristics of the product. Different types of waxes possess unique molecular structures that influence their melting temperature and ability to hold and disperse fragrance oils.
Paraffin: The Conventional Wax
Paraffin wax is a soft, colorless, or white solid derived from petroleum, making it a byproduct of the crude oil refining process. Its chemical structure consists of a mixture of solid straight-chain alkanes. This composition gives paraffin a dense structure that has made it the most widely used wax in the candle industry.
The melting point of paraffin wax generally ranges from 46°C to 68°C, depending on its degree of refinement. This high melting point allows paraffin to achieve an excellent hot scent throw. The structure of paraffin also makes it highly effective at retaining both color dyes and fragrance oils within the solid wax matrix.
Paraffin’s crystalline structure makes it a versatile material suitable for various candle types, including pillars, votives, and containers. Manufacturers can adjust the wax’s hardness and melt characteristics by using different grades of paraffin, which are separated based on their oil content and purity. Fully-refined paraffin wax, for example, has a very low oil content, resulting in a cleaner-burning product.
Natural Plant-Derived Waxes
A diverse category of waxes is derived from vegetation, offering alternatives to petroleum-based options, with soy wax being the most prevalent. Soy wax is produced from soybean oil, which is extracted from soybeans. The key process is hydrogenation, where hydrogen is introduced to the liquid oil, converting unsaturated fatty acids into saturated ones.
This chemical process increases the oil’s melting point, solidifying it into a wax suitable for candlemaking. Soy wax typically has a lower melting point than paraffin, which results in a slower, more even burn and a cleaner burn profile. Its softer nature makes it best suited for container candles, though it may yield a slightly weaker hot scent throw compared to paraffin.
Other plant-based alternatives include coconut wax, which is sourced from coconut oil and praised for its superior fragrance dispersion and extended burn duration. It is frequently blended with other waxes due to its naturally delicate and soft consistency. Palm wax is made from palm oil and is known for its unique crystalline structure that creates a distinctive “feathered” appearance in the finished candle. However, palm wax is subject to scrutiny due to environmental concerns related to its sourcing.
Beeswax and Other Essential Elements
Beeswax is a natural wax produced by worker honeybees and harvested from their honeycombs. It is one of the oldest materials used for candlemaking, possessing a unique, subtle honey-like aroma due to traces of pollen and nectar retained within the wax. Beeswax has a high melting point, around 62°C to 65°C, which contributes to its long, slow burn time and minimal dripping.
Beyond the wax itself, several other components are essential to a functional candle. The wick is most commonly made from braided cotton fibers. Wicks may also incorporate materials like paper or wood, or a core of zinc or tin, to provide rigidity and control the flame size.
Additives are used to modify the wax’s characteristics and enhance the candle’s aesthetic and scent:
- Fragrance oils are blended into the melted wax to provide the desired aroma.
- Dyes are added for color.
- Other compounds, such as stearic acid, a hardener, may be used to increase the wax’s density and opacity.
- Polymers like Vybar can be included to improve scent throw and color retention.