Liquid 2-hydroxy-4-alkoxybcnzophenones. forexample 2-hydroxy-4-isooctyloxybenzophenone, have been found lo be surprisingly highly effective for the light stabilization of candle wax. Candles are widely used to provide accent lighting as well as functioning as delivery systems for fragrances. However, candles and their component substances (wax, fragrances, colorants, etc.) arc subject to degradation when exposed to light. Undesirable changes occurring as a result of degradation include color fading and a loss orchangc of fragrance. The stabilization of candle wax against the effects of light using ultraviolet absorbers and other additives (including hindered amine light stabilizers, benzoate light stabilizers, and hindered phenolic antioxidants) is well known in the art. An example of an ultraviolet absorber trut has been employed for the stabilization of candlewaxis 2-hydroxy-4-octyloxybenzophenone. Chemical Abstract Service (CAS) No. 1843-05-6, a solid with a melting point of 47-49℃. Surprisingly, it has been found that candle wax can be more effectively stabilized by the addition of selected liquid 2-hydroxybenzophenone ultraviolet absorbers as compared lo candle wax stabilized with convcnlional solid 2-hydroxyhenzophenone ultraviolet absorbers. Liquid 2-hydroxybenzophenone ultraviolet absorbers found to be particularly advantageous for use in the light stabilization ofcandle wax are the 2-hydroxy-4-alkoxybcnzophcnoncs. where the alkoxy group comprises a mixture of randomly branched alkyl groups ("isoalkyl groups") having from about 6 lo about 12 carbon atoms. The compounds, methods for Iheir preparation, and stabilized polymer compositions comprising them are disclosed in US Patent Nos. 3.658.910 and 3,729.442. Most preferably, the liquid benzophenone ultraviolet absorber is 2-hydroxy-4-isooctyloxybenzophenonc, CAS No. 33059-05-1. Amounts of Ihe liquid 2-hydroxybenzophcnonc ultraviolet absorbers, which arc effective for the: stabilization of candle wax range between 0.01 and 10% by weight, preferably between 0.1 to 2% by weight, and most preferably bet ween 0.1 and 1% by weight. The liquid 2-hydroxybcnzophenone ultraviolet absorbers may be used either alone or in combination with one or more other types of stabilizing additives, including but not limited to conventional solid ultraviolet absorbers, hindered amine light stabilizers (HALS), benzoate light stabilizers (alkyl and arylesters of 3,5-di-tert-buty-4-hydroxybenzoic acid), and hindered phenolic antioxidants. Waxes suitable for use in candles include animal waxes such as beeswax, vegelable waxes such as soy wax, petroleum waxes such as paraffin wax, and synlhelic waxes. The waxes may be while or natural in color or contain added colorants such as dyes and pigments. The waxes may also be unscented or scented by the addition of fragrances.
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