Candle wax

Abstract

The invention relates to a candle wax composition, comprising one or more lauric fats and a plant-based oil and / or a plant-based wax. In addition, the present invention relates to a method of producing a candle wax composition, as well as the use of such candle wax compositions to reduce the formation of frosting and improve adhesion of the candle wax composition to glass.

Description

[0001] Candle Wax

[0002] FIELD OF THE INVENTION

[0003] The invention relates to a candle wax composition comprising one or more lauric fats and a plant-based oil and / or a plant-based wax. In addition, the present invention relates to a method of producing a candle wax composition, as well as the use of such candle wax compositions to reduce the formation of frosting and to improve adhesion of the candle wax composition to glass.

[0004] BACKGROUND

[0005] Candles have been used as a means for providing illumination since early civilization. Traditionally, candle bodies were formed from tallow and beeswax, however following the industrial revolution, candles were more commonly formed from paraffin wax, a byproduct formed in the production of gasoline, as these materials were less expensive and more readily available. However, in recent years, increased awareness of the environmental impact of using non-renewable fossil fuel-based materials has driven research to look at alternative materials for forming candles.

[0006] One possible solution is to return to using more traditional materials, such as beeswax, however these materials are less economically viable for producers. In addition, beeswax for example is considered to provide a poorer burn performance compared to paraffin wax, and so the use of more traditional materials may be less desirable to the consumer.

[0007] A candle formed from a renewable, environmentally friendly material, providing a burn performance similar to that of paraffin, would be desirable. Unfortunately, previous attempts to formulate candle wax compositions from vegetable oil-based materials have been relatively unsuccessful as the resulting products commonly comprised unacceptable defects. Such defects include cracking within the candle formed, air pocket formation, product shrinkage, undesirable blooming / frosting due to crystallisation of triglycerides and fatty acids, poor container adhesion, poor burning performance and / or reduced shelf life.

[0008] There are fundamental differences in the inherent properties of saturated triglycerides present in a renewable, plant-based oil or wax, compared to straight chain aliphatic hydrocarbons found in paraffin wax. Triglycerides exhibit polymorphic behavior, and so under rapid cooling, less stable and less molecularly dense crystals form initially, having a lower melting point. Through heating and cooling cycles these crystals can be rearranged to a more stable polymorph structure. Rearrangement of the polymorph structure can result in the formation of cracks in the candle body and bloom / frost formation. The presence of such defects increases the rejection percentage of products during production, thereby reducing overall value and increasing costs to the producer. Accordingly, numerous attempts have been made in order to overcome these issues.

[0009] For example, EP 2,845,895 discloses a candle formed from a fatty acid wax composition comprising a crystallisation inhibitor additive. In particular, the additive is selected from at least one homopolymer of a monomer of formula R1-CH=CR3R4(X), or at least one copolymer of the monomers of formula (X), stereoisomers and mixtures thereof. R1is selected from hydrogen, -C(=O)-OR5, and -CH2-C(=O)-OR5, R3is selected from hydrogen, -CH3, -C(=O)-OR5, and -CH2-C(=O)-OR5, R4is selected from -C(=O)-OR5, -O-C(=O)-R5, and -CH2-C(=O)-OR5, and R5is Ci2 to 22 alkyl. Whilst the use of a crystallisation inhibitor may reduce or prevent blooming, the inclusion of such additives increases both the time and cost of producing a plant-based candle wax.

[0010] An alternative plant-based candle wax is disclosed in US 6,599,344, which consists essentially of at least 85% partially hydrogenated soybean oil having an iodine value of between 49 and 53 and a melting point of between 122 and 128 degrees Fahrenheit (50 to 53.3°C); 0 to 4% synthetic wax formed by polymerising alpha olefins under free radical conditions to form a highly branched polymer; 0 to 4 % of a second hydrogenated vegetable or petroleum oil; 0 to 10 % fragrance; and 0 to 3 % dye. US ‘344 states that the plant-based candle wax formed can accommodate moderate variations in temperature and environment without sagging, cracking or otherwise physically degrading. In addition, US ‘344 also teaches that the composition burns without the production of soot, and cleanly melts away from the container walls. However, this plant-based candle wax does not address the issue of blooming / frosting.

[0011] Thus, there remains a need for providing a more cost-effective plant-based candle wax which prevents, delays or reduces the formation of crystal blooming. Furthermore, it would be desirable to provide a method of forming a plant-based candle wax composition which addresses at least some of the other known aesthetic issues associated with such materials, for example providing improved adhesion with containers and / or reduced product shrinkage.

[0012] SUMMARY OF THE INVENTION

[0013] According to a first aspect of the invention, there is provided a candle wax composition comprising: a. from 10 to 90 wt% of one or more lauric fats; and b. a plant-based oil and / or a plant-based wax forming the remaining portion of the composition; wherein the composition comprises from 4 to 45 wt% lauric acid (C12:0) and from 0.1 to 20% myristic acid (C14:0) and has an iodine value of from 5 to 75.

[0014] The present invention is based on the surprising discovery that candle wax compositions containing higher amounts of lauric acid and myristic acid have increased stability, resulting in reduced frosting. In addition, candle bodies formed using candle wax compositions in accordance with the present invention were found to possess fewer defects, thereby reducing the percentage of rejected products, and increasing cost efficiency. In particular, it has been found that compositions in accordance with the present invention prevent, reduce and / or delay frosting as well as improve adhesion to containers, for example improve glass adhesion.

[0015] The iodine value of the candle wax composition is from 5 to 75. The iodine value provides an indication of the degree of unsaturation in an oil or fat. The number provided is the number of grams of iodine absorbed by 100g of an unsaturated fat or oil or a blend of fats and oils. Accordingly, a low iodine value indicates a higher level of saturation, for example fully hydrogenated vegetable oils typically have iodine values of from 0 to 4.

[0016] The iodine value can be determined by the WIJS method as set out in the American Oil Chemists’ Society (A.O.C.S. Cd 1-25) or as set out in ASTM D5554-15(2021).

[0017] It is conceived that both the one or more lauric fats and the plant-based oil and / or plantbased wax may be partially hydrogenated. Alternatively, the one or more lauric fat may be fully hydrogenated and the plant-based oil and / or plant-based wax may be selected from a partially hydrogenated or non-hydrogenated composition. As a further alternative, the plant-based oil and / or plant-based wax may be fully hydrogenated and the one or more lauric fats comprise a partially hydrogenated composition.

[0018] Preferably, the candle wax composition has an iodine value of from 15 to 60, more preferably from 25 to 50.

[0019] In some embodiments, the candle wax composition comprises from 8 to 40 wt% lauric acid (C12:0), preferably from 12 to 35 wt% lauric acid. It is well-known within this field that lauric fats are vegetable fats comprising higher amounts of lauric acid (as illustrated in Table 1 - examples from “The Lipid Handbook”, 1994). Table 1

[0020] However, lauric acid present in the candle wax composition may not be solely derived from the one or more lauric fats. Lauric acid present in the composition may be at least partially derived from the plant-based oil and / or a plant-based wax present. In other examples, the lauric acid present in the candle wax composition may be solely derived from the one or more lauric fats present.

[0021] In addition to containing higher amounts of lauric acid, lauric fats generally further comprise myristic acid (as illustrated in Table 1). Accordingly, in embodiments of the present invention, the candle wax composition comprises both lauric acid (C12:0) and myristic acid (C14:0), for example myristic acid may be present in an amount of at least 0.1 wt% of the composition. Preferably, the candle wax composition comprises from 1 to 15 wt% myristic acid, more preferably from 5 to 12 wt% myristic acid.

[0022] The one or more lauric fats may be selected from palm kernel oil, coconut oil, babassu oil, cohune oil, murumuru oil, ouricury oil, tucum oil and genetically modified canola oil, such as Laurical ® or any fraction thereof and any mixtures thereof. In preferred compositions, the one or more lauric fats are selected from palm kernel oil and / or coconut oil, any fractions thereof or any mixtures thereof.

[0023] It is considered to be well within the understanding of the person of skill in the art to select a suitable fraction of one or more lauric fats for use in accordance with the present invention. For example, a palm kernel fraction may be selected from a palm kernel olein fraction or palm kernel stearin fraction. Similarly, a coconut oil fraction may be selected from a coconut oil olein fraction or a coconut oil stearin fraction. Thus, the one or more lauric fats, any fractions thereof or any mixtures thereof, may be at least partially hydrogenated. Likewise, at least one of the one or more lauric fats, any fractions thereof or any mixtures thereof, may be fully hydrogenated.

[0024] Of course, the amount of hydrogenated and partially-hydrogenated fats and oils within the composition may be varied in order to control the melting point and the shelf life of the candle wax composition formed. In general, the melting point of candle wax composition is from 35 °C to 80 °C. In some examples, the candle wax composition may have a melting point of from 35 to 65 °C, preferably from 40 to 60 °C.

[0025] Alternatively or in addition, interesterification reactions can be used to alter the physical properties of fats and oils. In particular, interesterification is known to alter the melting temperature, crystallisation properties and shelf life of fats and oils.

[0026] The term “interesterification” as used herein should be understood as the process of replacing one or more of the fatty acid moieties of a triglyceride with another fatty acid moiety or exchanging one or more fatty acid moieties from one triglyceride molecule to another or exchanging the position of a fatty acid within one triglyceride to another position in the same triglyceride. A fatty acid moiety may be understood as a free fatty acid, a fatty acid ester and / or a fatty acid anhydride. The interesterification process may be an enzymatic interesterification or chemical interesterification. Both chemical interesterification and enzymatic interesterification processes are well known within this field.

[0027] Accordingly, at least one of the one or more lauric fats, any fractions thereof or any mixtures thereof, may be interesterified. Likewise, all of the one or more lauric fats, any fractions thereof or any mixtures thereof may be interesterified.

[0028] Alternatively or in addition, the plant-based oil and / or plant-based wax may be interesterified.

[0029] The composition may comprise from 15 to 80 wt% of the one or more lauric fats, any fractions thereof or any mixtures thereof, and preferably from 20 to 60 wt% of the one or more lauric fats, any fractions thereof or any mixtures thereof.

[0030] The term "plant-based oil" as used herein is intended to include any fat or oil derived from plants. The term “fat” as used herein refers to glyceride fats and oils containing fatty acid acyl groups and does not imply any particular melting point. The term “oil” is used synonymously with “fat” herein. Preferably, the plant-based oil is selected from an at least partially hydrogenated or fractionated plant-based oil, including an at least partially hydrogenated or fractionated cottonseed oil, sunflower oil, safflower oil, corn oil, olive oil, peanut oil, rapeseed oil, almond oil, jojoba oil, soybean oil, avocado oil, sesame oil, castor oil, palm oil, shea butter, cocoa butter, or combinations thereof, preferably the plant-based oil is selected from soybean oil, shea butter, or a fraction thereof, for example soybean oil or a fraction thereof.

[0031] Again, it is considered to be well within the understanding of the skilled person to select a suitable fraction of a plant-based oil for use in accordance with the present invention.

[0032] The term "plant-based wax" is intended to include substances extracted from plants that comprise wax esters and are solid or semi-solid at room temperature and exhibit a crystalline structure. In some embodiments, the plant-based wax is selected from carnauba wax, candelilla wax, and rice bran wax.

[0033] The candle wax composition may comprise both a plant-based oil and plant-based wax. The ratio of the plant-based oil to plant-based wax may be varied in order to control the melting temperature of the resulting composition. In general, the ratio of plant-based oil to plant-based wax in the composition may be from 5:1 to 1 :5, preferably 4:1 to 1 :4, more preferably 2.5:1 to 1 :2.5, for example the plant-based oil and plant-based wax may be present in a ratio of 1 :1.

[0034] The solid fat content (SFC) of a composition is the percent of solid fat present at a specified temperature. SFC is typically measured using pulsed nuclear magnetic resonance (NMR). In particular, SFC can be measured in accordance with ISO 8292-1.

[0035] In some embodiments, the candle wax composition has a solid fat content (SFC) N10 of 70 % or more, preferably 75 % or more, more preferably 80 % or more, measured in accordance with ISO 8292-1.

[0036] Alternatively or in addition, the candle wax composition may have a solid fat content (SFC) N20 of 55 % to 90 %, preferably 60 % to 85 %, more preferably 65 % to 85 %, measured in accordance with ISO 8292-1.

[0037] Alternatively or in addition, the candle wax composition may have a solid fat content (SFC) N30 of 35 % to 70 %, preferably 37 % to 65 %, more preferably 40 % to 60 %, measured in accordance with ISO 8292-1. Alternatively or in addition, the candle wax composition may have a solid fat content (SFC) N35 of 15 % to 55 %, preferably 20 % to 50 %, more preferably 25 % to 45 %, measured in accordance with ISO 8292-1.

[0038] Alternatively or in addition, the candle wax composition may have a solid fat content (SFC) N40 of 5 % to 40 %, preferably 7 % to 35 %, more preferably 10 % to 30 %, measured in accordance with ISO 8292-1.

[0039] In preferred examples, the candle wax composition has the following properties:

[0040] • a solid fat content (SFC) N10 of 70 % or more;

[0041] • a solid fat content (SFC) N20 of 55 to 90 %;

[0042] • a solid fat content (SFC) N30 of 35 to 70 %;

[0043] • a solid fat content (SFC) N35 of 15 to 55 %; and

[0044] • a solid fat content (SFC) N40 of 5 to 40 %.

[0045] In a particularly preferred example, the candle wax composition has the following properties:

[0046] • a solid fat content (SFC) N10 of 80 % or more;

[0047] • a solid fat content (SFC) N20 of 65 to 85 %;

[0048] • a solid fat content (SFC) N30 of 40 to 60 %;

[0049] • a solid fat content (SFC) N35 of 25 to 45 %; and

[0050] • a solid fat content (SFC) N40 of 10 to 30 %.

[0051] The candle wax composition may further comprise a minor amount of an alternative wax composition, for example a synthetic wax, such as polyethylene or polypropylene, or a petroleum-based wax, such as paraffin wax. The inclusion of further wax compositions may be used to alter the physical properties of the candle wax composition, for example the presence of a minor amount of paraffin wax can improve the thermal stability of the resulting composition. In some examples, the alternative wax composition may be selected from a paraffin wax composition in order to align the physical properties of the overall composition closer to that of paraffin wax.

[0052] The term “minor” as used herein is intended to include amounts of less than 50 wt%, preferably 0.1 to 45 wt%, more preferably 0.5 to 30 wt% of the composition. By way of a preferred example, the candle wax composition may further comprise 30 to 45 wt% paraffin wax. By way of another preferred example, paraffin wax may be present in an amount of from 0.1 to 5 wt%, preferably from 0.5 to 2 wt% of the composition.

[0053] However, in some examples, the candle wax composition may preferably be free of petrochemical derived products.

[0054] Plant-based oils comprise triglycerides as a major component, with lesser amounts of diglycerides, monoglycerides and free fatty acids.

[0055] Triglycerides are ester compounds in which glycerol is linked to three fatty acids and have the general formula:

[0056] R1, R2, and R3are fatty acid chains and may be the same or different.

[0057] The types and amounts of triglycerides present in the plant-based oils may be determined for example based on molecular weight differences (Carbon Number (CN)), as set out in AOCS Ce 5-86. The notation triglyceride CNxx indicates triglycerides having xx carbon atoms in the fatty acyl groups, e.g., CN54 includes tristearin. Amounts of triglycerides specified with each carbon number (CN) is provided as percentages by weight based on total triglycerides of CN26 to CN62 present in the fat composition, as is customary within this field.

[0058] Monoglycerides which may be present in plant-based oils include, but are not limited to, glyceryl monooleate, glyceryl monolaurate, and glyceryl monostearate. Examples of diglycerides include, without limitation, glyceryl dioleate, glyceryl dilaurate and glyceryl distearate.

[0059] Fatty acids which may be present in plant-based oils include, but are not limited to lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid and combinations thereof. The candle wax composition may comprise at least 55 wt% of triglycerides, preferably at least 60 wt% of triglycerides, more preferably at least 70 wt% of triglycerides.

[0060] The candle wax composition may further comprise one or more polyol fatty acids and / or partial polyol esters. In particular, where present, the one or more polyol fatty acids and / or partial polyol esters may be present in an amount of less than 15 wt%, preferably less than 10 wt%, more preferably less than 5 wt% of the candle wax composition.

[0061] The polyol fatty acids may include at least two, preferably at least three, hydroxy groups per molecule. Typically, polyol fatty acids have no more than 6 hydroxy groups per molecule and include up to 10 carbon atoms, preferably no more than 6 carbon atoms. Examples of suitable aliphatic polyols for forming polyol fatty acids include glycerol, alkylene glycols (e.g., ethylene glycol, diethylene glycol, triethylene glycol and neopentylglycol), pentaerythritol, trimethylolethane, trimethylolpropane, sorbitan and sorbitol. Suitable alicyclic polyols include cyclohexanediols and inositol as well as natural cyclic polyols such as glucose, galactose and sorbose.

[0062] The partial polyol esters have one or more unesterified hydroxyl groups with the remaining hydroxy groups esterified by a fatty acyl group. The fatty acyl groups (“ — C(O)R”) in the partial esters includes an aliphatic chain (linear or branched), preferably a C14 to C30 aliphatic chain (linear or branched).

[0063] The partial polyol ester may be selected from monoglycerides, diglycerides or combinations thereof, preferably, the partial polyol ester is selected from a monoglyceride.

[0064] In particular examples, the partial polyol ester is selected from glycerol, alkylene glycols such as ethylene glycol, diethylene glycol, triethylene glycol and neo-pentylglycol, pentaerythritol, trimethylolethane, trimethylolpropane, sorbitan, sorbitol, alicyclic polyols such as cyclohexanediols and inositol, and natural cyclic polyols such as glucose, galactose and sorbose.

[0065] The candle wax composition may further comprise at least one additive selected from the group consisting of: coloring agents, scenting agents, surfactants, emulsifiers and combinations thereof. The at least one additive may be present in an amount of from 0.1 to 15 wt% of the composition, preferably from 0.5 to 10 wt% of the composition, more preferably from 1 to 5 wt% of the composition. Where more than one additive is present, the total amount of additive in the composition is as defined above. Where present, the colorant may be selected from one or more pigments and / or dyes. Particularly suitable colorants include titanium dioxide, zinc oxide white, copper, bronze, aluminium metal powders and flakes, phthalocyanine blue, phthalocyanine green, yellow and red pigments of the benzimide azoIone group. In preferred examples, the colorant may be present in an amount of from 0.1 to 5 wt% of the composition.

[0066] Examples of scenting agents suitable for use in a candle wax composition as defined herein include, but are not limited to, sandalwood oil, civet oil, cedarwood oil, patchouli oil, bergamot oil, germanium oil, rose oil, citronella oil, eugenol, geraniol, geranyl acetate, isoeugenol, isobornyl acetate, linalyl acetate, linalool, methyl ethyl ketone, methylionone, phenylethyl alcohol, and various other compounds of aldehydes, ketones, esters, alcohols, terpenes or the like. The scenting agent may be an insect repellent such as citronellal or a therapeutic agent such as menthol or eucalyptus. In preferred examples, the scenting agent may be present in an amount of from 0.1 to 10 wt% of the composition, more preferably from 0.5 to 5 wt% of the composition.

[0067] The surfactant may preferably be selected from a non-ionic surfactant. Non-ionic surfactants typically have a hydrophobic base, such as a long chain alkyl group or an alkylated aryl group, and a hydrophilic group comprising ethoxy and / or propoxy moieties. Surfactants that may be used in accordance with the present invention include, but are not limited to, ethoxylated alkylphenols, ethoxylated and propoxylated fatty alcohols, polyethylene glycol ethers of methyl glucose, polyethylene glycol ethers of Sorbitol, ethylene oxide-propylene oxide block copolymers, ethoxylated esters of fatty (Cs-Cs) acids, condensation products of ethylene oxide with long chain amines or amides, condensation products of ethylene oxide with alcohols, and mixtures thereof.

[0068] Other suitable non-ionic surfactants include non-ionic esters or ethers having a polyoxy alkylene moiety (e.g., polyoxyethylene) and / or containing a polyhydroxy compound, such as glycerol, sorbitol, or other hydrophilic moiety, ethoxylates, including fatty acid ester ethoxylates, fatty acid ether ethoxylates, and ethoxylated sugar derivatives (e.g., ethoxylated fatty acid polyesters, ethoxylated fatty acid sorbitan esters, and the like). Representative ethoxylated fatty acid sorbitan esters include, for instance, polyoxyethylene sorbitan laurate (i.e., Polysorbate-20 (HLB of 16.7) and Polysorbate-21 (HLB of 13.3)), polyoxyethylene sorbitan palmitate (i.e., Polysorbate-40 (HLB of 15.6)), polyoxyethylene sorbitan stearate (i.e., Polysorbate-60 (HLB of 14.9) and Polysorbate-61 (HLB of 9.6)), polyoxyethylene sorbitan tristearate (i.e., Polysorbate-65 (HLB of 10.5)), polyoxyethylene sorbitan oleate (i.e., Polysorbate-80 (HLB of 15.0) and 81 (HLB of 10.0)), polyoxyethylene sorbitan trioleate (i.e., Polysorbate-85 (HLB of 11.0)), and so forth.

[0069] Cationic surfactants include imidazolines, diethyl amine, or ethoxylated amines, such as tallow amine TAM-5 or TAM-1 5.

[0070] Where the candle wax composition further comprises a surfactant, the surfactant may be present in an amount of from 0.1 to 10 wt% of the composition, preferably from 0.5 to 5 wt% of the composition. Of course, the candle wax composition may comprise a combination of two or more surfactants. In these examples, the total amount of surfactant present in the candle wax composition may be from 0.1 to 10 wt%, preferably from 0.5 to 5 wt% of the composition.

[0071] Preferably, the emulsifier may be selected from one or more non-ionic emulsifiers.

[0072] Non-ionic emulsifiers suitable for use in candle wax compositions as defined herein, include, but are not limited to, ethoxylated aliphatic alcohols, polyoxyethylene surfactants, carboxylic esters, polyethylene glycol esters, anhydrosorbital esters, derivatives of anhydrosorbitol esters, glycol esters of fatty acids, carboxylic amides, monoalkanolamine condensates and polyoxyethylene fatty acid amines. For example, the non-ionic emulsifier can include fatty alcohols, cetyl alcohols, stearyl alcohols, cetostearyl alcohols, oleyl alcohols, polyoxyethylene glycol alkyl ethers (Brij), polyoxypropylene glycol alkyl ethers, glucoside alkyl ethers, polyoxyethylene glycol octylphenol ethers, polyoxyethylene glycol alkylphenol ethers, glycerol alkyl esters, polyoxyethylene glycol sorbitan alkyl esters, sorbitan alkyl esters, cocamide MEAs, cocamide DEAs, dodecyldimethylamine oxides, block copolymers of polyethylene glycol, and polypropylene glycol.

[0073] In preferred examples the candle wax composition does not comprise an antifoaming agent.

[0074] The candle wax composition may be stored prior to use in forming a candle body. Thus, the candle wax composition may comprise any suitable shape or structure to allow for storage of the candle wax composition. For example, the candle wax composition may be in the form of flakes, beads, pellets, shavings, ribbons or sheets. Alternatively, the candle wax composition may be extruded or moulded into any suitable shape.

[0075] According to a second aspect of the invention, there is provided a candle comprising: a. a solidified candle body; and b. a candlewick extending into the candle body, wherein the solidified candle body is formed from a candle wax composition as defined above.

[0076] The candle may be formed by heating a candle wax composition as defined herein above the melting temperature such that a liquid candle wax composition is formed. Any suitable process known in the art may be used to form the liquid candle wax composition, for example the candle wax may be heated using a water bath or oil bath, a heating jacket, microwave assisted heating or electrical heating. Preferably, the candle wax composition is stirred whilst heating, for example, using a static mixer or a mechanically stirred mixing vessel, in order to improve the efficiency of heat transfer throughout the candle wax, thereby reducing the time required to produce a liquid composition.

[0077] The candle wax composition may be maintained in a liquid form for a period of from 1 minute to 24 hours, preferably from 5 minutes to 15 hours, more preferably 10 minutes to 10 hours before proceeding to form the candle. Whilst the candle wax is maintained in a liquid form, stirring may continue to ensure homogeneous heating.

[0078] The term candle as used herein is used to refer to a shaped solid block of wax with a central wick protruding from a surface of the candle. The wick is to be lit and burnt using the candle wax of the candle as fuel. Preferably, the wick of the candle also extends throughout the length of the candle from where the wick protrudes at the top of the candle to the bottom of the candle.

[0079] A variety of different types of candle are known in the art. These include molded candles, crown candles, container candles, dipping candles and pillar candles.

[0080] Molded candles and crown candles are candles that are formed by pouring molten wax into a mold; inserting a wick into the molten wax and then allowing the wax composition to solidify by crystallisation. The crystallisation behaviour of the candle wax is important for this application. If the wax crystallises too quickly then excessive shrinkage of the wax composition will occur in the mold leading to uneven surfaces of the candle and a reduced aesthetic appeal. This typically occurs with candle wax compositions comprising only fully hydrogenated vegetable oils, for example candle wax compositions having an iodine value of 0 to 4. In contrast, where the wax composition is too soft and crystallizes too slowly, insufficient shrinkage of the wax composition will occur in the molding process leading to adhesion of the composition to the mold once solidified. A container candle is a candle where the solid wax is contained within a container. The candle is produced by pouring molten wax into the container; inserting the wick into the molten wax; and then allowing the molten wax to solidify so as to form the candle. Again, where crystallisation occurs too rapidly, candle wax may shrink causing the composition to pull away from the inner surface of the container. These effects result in the presence of unwanted gaps between the container and the candle. Such defects increase the rejection percentage of products during production, thereby reducing overall value and increasing costs to the producer.

[0081] Dipping candles are produced by dipping a wick into molten wax and then removing the wick so that it is coated with a thin layer of wax which is allowed to solidify. The dipping process is then repeated so as to build up successive layers of the wax until the candle is of the desired thickness. The crystallisation behaviour of the candle wax is also important in the production of dipping candles.

[0082] Pillar candles are formed by subjecting solid granules, powders or flakes of a wax composition to high pressures which causes the granules to coalesce into a solid mass that is the candle.

[0083] The different ways in which these candle types are produced can mean that different optimum properties for the candle wax are desirable for each type of candle. For example, in the case of container, molded and crown candles, the crystallisation behaviour (i.e. how the wax crystallises on cooling) of the wax composition is important, whereas for pillar candles, this is less of a consideration. In the case of pillar candles, how the solid wax granules behave under the high pressures used in the production processes is more important.

[0084] In addition to the above considerations, as discussed above, candles produced using plant-based wax composition are known to be more susceptible to undesirable frosting / blooming (i.e. conversion of the fat crystals from one polymorphic form to another).

[0085] It has been surprisingly found that candle wax compositions containing higher amounts of lauric acid and myristic acid have increased stability, resulting in the prevention or reduction of frosting. In addition, the candle wax compositions as defined herein provide increased adhesion to container surfaces, thereby reducing defects commonly observed in container candles.

[0086] Accordingly, the candle wax compositions defined herein are considered to be particularly suitable for forming container candles. In forming a candle in accordance with the present invention, the candlewick may be contacted with the liquid candle wax composition such that a portion of the candlewick is coated with the liquid candle wax composition. The candle wax composition coating is then allowed to cool on the surface of the candlewick. The steps of i) contacting the candlewick with the liquid candle wax composition so that a portion of the candlewick is coated with the liquid candle wax composition and ii) allowing the coating layer to cool, may be repeated until a suitable candle body thickness is formed around the candlewick.

[0087] Alternatively, a candle in accordance with the present invention may be formed by i) positioning the candlewick within a mould, ii) heating a candle wax composition as defined herein to a temperature above its melting temperature so that a liquid candle wax composition is formed, iii) pouring the liquid candle wax composition into the mould, and iv) allowing the liquid candle wax composition to cool and solidify.

[0088] In some embodiments, the mould is used solely to shape the candle body formed, and so following step iv) the candle formed may be removed from the mould. In other embodiments, the mould may also be a container for the candle, and so it is not necessary to remove the candle body from the container once the liquid candle wax composition has solidified.

[0089] In preferred examples, the candle is arranged within a container, wherein the container is preferably formed from a glass, metal, wood, ceramic or plastic material.

[0090] The candlewick may be formed from any conventional material known for use in candles, such as natural and synthetic fibres, for example cotton, hemp, wood, or paper.

[0091] The candle can have more than one wick. For example, the candle can have two wicks, three wicks, four wicks, five wicks, six wicks, seven wicks, eight wicks, nine wicks or ten wicks.

[0092] According to a third aspect of the invention, there is provided a method of producing a candle wax composition, wherein the method comprises the steps of: a. providing one or more lauric fats in an amount of from 10 to 90 wt% of the composition; b. providing a plant-based oil and / or a plant-based wax forming the remainder of the composition; c. heating the one or more lauric fats and plant-based oil / wax to a temperature of from 40 to 90°C to form a liquid composition; d. mixing the liquid composition of one or more lauric fats and plant-based oil / wax to form a homogenous composition; e. cooling the homogeneous composition to room temperature, wherein the composition comprises from 4 to 45 wt% lauric acid (C12:0) and from 0.1 % to 20% myristic acid (C14:0) and has an iodine value of from 5 to 75.

[0093] Preferably, the one or more lauric fat, plant-based oil and / or plant-based wax are as defined above.

[0094] By way of example, the one or more lauric fats and plant-based oil / wax may be combined prior to heating to a temperature of 40 to 90°C. Preferably, the one or more lauric fats and plant-based oil / wax are mixed in order to improve the homogeneity of the components prior to heating. For example, the plant-based oil / wax may be in a form suitable to enhance mixing of the one or more lauric fats and plant-based oil / wax prior to heating, such as in the form of pellets, beads or shavings.

[0095] Alternatively, the one or more lauric fats and plant-based oil / wax are first heated to a temperature of 40 to 90°C before the respective liquid compositions are combined. In some examples, heating the one or more lauric fats and plant-based oil / wax separately reduces the time required for the individual components to reach the required temperature and the overall time for forming the candle wax composition.

[0096] In preferred examples, the one or more lauric fats and plant-based oil / wax may be heated to a temperature of 50 to 85°C, more preferably a temperature of 55 to 75 °C.

[0097] In step d., the step of mixing the liquid composition of one or more lauric fats and plantbased oil / wax proceeds for a period of from 1 minute to 15 hours, preferably from 10 minutes to 10 hours, more preferably from 30 minutes to 5 hours.

[0098] Mixing may be carried out using any suitable device, for example by passing the combined one or more lauric fats and plant-based oil / wax through a mixing valve, by using a static mixer or by using a mechanically stirred mixing vessel. Alternatively, mixing may be induced by turbulent flow along a length of pipeline. Preferably, mixing is carried out by passing the combined one or more lauric fats and plant-based oil / wax through a mixing valve. This allows the components to be thoroughly mixed producing a homogenous composition. The pressure differential across the mixing valve may be, for example, from 1 to 20 psi, more preferably from 4 to 17 psi, and most preferably from 7 to 14 psi.

[0099] In step e., the step of cooling the homogenous composition to room temperature may be performed by any suitable means known in the art, for example ambient cooling or cooling the homogenous composition using fans, a cooling jacket or a temperature-controlled water bath.

[0100] By way of example, the homogenous composition of step e. may be cooled via a heat exchanger with the one or more lauric fats and plant-based oil / wax of step c. By reusing the heat extracted from the homogenous composition the cost of the overall process can be further reduced.

[0101] Preferably, the one or more lauric fats and plant-based oil / wax are selected such that the solid fat content (SFC) of the resulting candle wax composition is as defined above.

[0102] In preferred examples, the candle wax composition formed has the following properties:

[0103] • a solid fat content (SFC) N10 of 70 % or more;

[0104] • a solid fat content (SFC) N20 of 55 to 90 %;

[0105] • a solid fat content (SFC) N30 of 35 to 70 %;

[0106] • a solid fat content (SFC) N35 of 15 to 55 %; and

[0107] • a solid fat content (SFC) N40 of 5 to 40 %.

[0108] In a particularly preferred example, the candle wax composition formed has the following properties:

[0109] • a solid fat content (SFC) N10 of 80 % or more;

[0110] • a solid fat content (SFC) N20 of 65 to 85 %;

[0111] • a solid fat content (SFC) N30 of 40 to 60 %;

[0112] • a solid fat content (SFC) N35 of 25 to 45 %; and

[0113] • a solid fat content (SFC) N40 of 10 to 30 %.

[0114] The method may further comprise the step of providing an alternative wax composition prior to heating to a temperature from 40 to 90 °C. The alternative wax composition may be selected from a synthetic wax, such as polyethylene or polypropylene, or a petroleumbased wax, such as paraffin wax. The inclusion of further wax compositions may be used to alter the physical properties of the candle wax composition, for example the presence of a minor amount of paraffin wax can improve the thermal stability of the resulting composition. In some examples, the alternative wax composition may be selected from a paraffin wax composition in order to align the physical properties of the overall composition with that of paraffin wax.

[0115] Paraffin wax may be added to the one or more lauric fats and plant-based oil / wax in an amount as defined above, prior to heating to a temperature from 40 to 90 °C.

[0116] The method may further comprise the step of providing one or more polyol fatty acids or partial polyol esters, prior to heating to a temperature from 40 to 90 °C.

[0117] The one or more polyol fatty acids and / or partial polyol esters may be as defined above.

[0118] Preferably, the one or more polyol fatty acids and / or partial polyol esters may be added to the one or more lauric fats and plant-based oil / wax in an amount of less than 15 wt%, preferably less than 10 wt%, more preferably less than 5 wt% of the candle wax composition.

[0119] According to a fourth aspect of the present invention, there is provided the use of a candle wax composition as defined herein for reducing the formation of frosting.

[0120] According to a fifth aspect of the present invention, there is provided the use of a candle wax composition as defined herein for improving the adhesion of candle wax to glass.

[0121] The present inventions will now be described with reference to the following non-limiting examples, and with reference to the accompanying drawings, in which:

[0122] Figures 1A to 1 C illustrate a candle formed from a candle wax composition in accordance with the present invention;

[0123] Figures 2A to 2D illustrate a candle formed from a candle wax composition in accordance with the present invention; and

[0124] Figures 3A and 3B illustrate a candle formed from a candle wax composition in accordance with the present invention.

[0125] EXAMPLES

[0126] The following examples are for illustrative purposes only and are not intended to limit the scope of the invention in any way. Example 1

[0127] A candle wax composition was produced by combining a fully hydrogenated palm kernel olein and a partially hydrogenated soybean oil in a 1 :1 ratio and adding distilled monoglyceride in an amount of 2 wt% of the final composition.

[0128] The components were heated to a temperature of 85°C and stirred until a generally homogeneous composition was formed.

[0129] The homogenous composition was poured into a glass container and allowed to cool to ambient temperature.

[0130] The fatty acid composition of the candle wax formula is provided in Table 2.

[0131] Table 2

[0132] The iodine value of the candle wax composition was measured as 26.8. As illustrated in Figures 1A to 1C the candle wax composition demonstrates good adhesion to the glass container. In addition, no evidence of frosting was observed upon intial cooling of the candle wax compositon. Throughout a monitoring period of 15 weeks, the candle wax composition displayed good container adhesion and no frosting was observed.

[0133] Example 2

[0134] A second candle wax composition was produced comprising 20 wt% palm kernel stearin, 77 wt% partially hydrogenated soybean oil and 3wt% of sorbitan tristearate.

[0135] The components were heated to a temperature of 85°C and stirred until a generally homogeneous composition was formed. The homogenous composition was cooled to a temperature of 75°C and poured into a glass container. The candle wax composition was then allowed to cool to ambient temperature in order to set.

[0136] The fatty acid composition of the candle wax formula is provided in Table 3.

[0137] Table 3

[0138] The iodine value of the candle wax composition was measured as 40.1 . Again, Figures 2A to 2D show that the candle wax composition adheres fully to the glass container. In addition, no evidence of frosting was observed upon intial cooling of the candle wax compositon. Throughout a monitoring period of 20 weeks, the candle wax composition displayed good container adhesion and no frosting was observed.

[0139] Example 3

[0140] A third candle wax composition was produced comprising 20 wt% fully hydrogenated coconut oil, 76 wt% partially hydrogenated soybean oil and 4 wt% distilled monoglyceride.

[0141] The components were heated to a temperature of 85°C and stirred until a generally homogeneous composition was formed.

[0142] The homogenous composition was cooled to a temperature of 75°C and poured into a glass container. The candle wax composition was then allowed to cool to ambient temperature in order to set.

[0143] The fatty acid composition of the candle wax formula is provided in Table 4.

[0144] Table 4

[0145] The iodine value of the candle wax composition was measured as 38. As illustrated in Figures 3A and 3B the candle wax composition demonstrates good adhesion to the glass container. In addition, no evidence of frosting was observed upon intial cooling of the candle wax compositon. Throughout a monitoring period of 4 weeks, the candle wax composition maintained good container adhesion and no frosting was observed.

Claims

Claims1 . A candle wax composition comprising: a. from 10 to 90 wt% of one or more lauric fats; and b. a plant-based oil and / or a plant-based wax forming the remaining portion of the composition; wherein the composition comprises from 4 to 45 wt% lauric acid (C12:0) and from 0.1 to 20% myristic acid (C14:0) and has an iodine value of from 5 to 75.

2. A candle wax composition according to Claim 1 , wherein the composition comprises from 8 to 40 wt% lauric acid.

3. A candle wax composition according to Claim 1 or 2, wherein the composition comprises from 12 to 35 wt% lauric acid.

4. A candle wax composition according to any preceding claim, wherein the composition comprises from 1 to 15 wt% myristic acid, preferably from 5 to 12 wt% myristic acid.

5. A candle wax composition according to any preceding claim, wherein the one or more lauric fats are selected from palm kernel oil, coconut oil, babassu oil, cohune oil, murumuru oil ouricury oil, tucum oil and genetically modified canola oil, such as Laurical ®, any fraction thereof and any mixtures thereof, preferably the one or more lauric fats are selected from palm kernel oil and / or coconut oil, any fractions thereof or any mixtures thereof.

6. A candle wax composition according to any preceding claim, wherein at least one of the one or more lauric fats, any fractions thereof or any mixtures thereof, is at least partially hydrogenated.

7. A candle wax composition according to any preceding claim, wherein at least one of the one or more lauric fats, any fractions thereof or any mixtures thereof, is fully hydrogenated.

8. A candle wax composition according to any preceding claim, wherein at least one of the one or more lauric fats, any fractions thereof or any mixtures thereof, is interesterified.

9. A candle wax composition according to any preceding claim, wherein the composition comprises from 15 to 80 wt% of the one or more lauric fats, any fractions thereof or any mixtures thereof.

10. A candle wax composition according to any preceding claim, wherein the composition comprises from 20 to 60 wt% of the one or more lauric fats, any fractions thereof or any mixtures thereof.

11. A candle wax composition according to any preceding claim, wherein the one or more lauric fats comprises palm kernel oil, preferably palm kernel olein or palm kernel stearin.

12. A candle wax composition according to any preceding claim, wherein the plantbased oil is selected from an at least partially hydrogenated or fractionated cottonseed oil, sunflower oil, safflower oil, corn oil, olive oil, peanut oil, rapeseed oil, almond oil, jojoba oil, soybean oil, avocado oil, sesame oil, castor oil, palm oil, shea butter, cocoa butter, or combinations thereof, preferably the plant-based oil is selected from soybean oil, shea butter, or a fraction thereof, for example soybean oil or a fraction thereof.

13. A candle wax composition according to any preceding claim, wherein the plantbased wax is selected from carnauba wax, candelilla wax, and rice bran wax.

14. A candle wax composition according to any preceding claim, wherein the composition has a solid fat content (SFC) N10 of 70 % or more, preferably 75 % or more, more preferably 80 % or more according to ISO 8292-1.

15. A candle wax composition according to any preceding claim, wherein the composition has a solid fat content (SFC) N20 of 55 % to 90 %, preferably 60 % to 85 %, more preferably 65 % to 85 % according to ISO 8292-1.

16. A candle wax composition according to any preceding claim, wherein the composition has a solid fat content (SFC) N30 of 35 % to 70 %, preferably 37 % to 65 %, more preferably 40 % to 60 % according to ISO 8292-1.

17. A candle wax composition according to any preceding claim, wherein the composition has a solid fat content (SFC) N35 of 15 % to 55 %, preferably 20 % to 50 %, more preferably 25 % to 45 % according to ISO 8292-1.

18. A candle wax composition according to any preceding claim, wherein the composition has a solid fat content (SFC) N40 of 5 % to 40 %, preferably 7 % to 35 %, more preferably 10 % to 30 % according to ISO 8292-1 .

19. A candle wax composition according to any preceding claim, wherein the composition has a solid fat content (SFC) N10 of 80 % or more, N20 of 65 to 85 %, N30 of 40 to 60 %, N35 of 25 to 45 % and N40 of 10 to 30 % according to ISO 8292-1.

20. A candle wax composition according to any preceding claim, wherein the composition further comprises a paraffin wax.21 . A candle wax composition according to Claim 20, wherein paraffin wax is present in an amount of 30 to 45 wt%.

22. A candle wax composition according to any preceding claim, wherein the composition comprises at least 55 wt% of triglycerides, preferably at least 60 wt% of triglycerides, more preferably at least 70 wt% of triglycerides.

23. A candle wax composition according to any preceding claim, wherein the composition further comprises one or more polyol fatty acid or partial polyol ester.

24. A candle wax composition according to Claim 23, wherein the polyol fatty acid or partial polyol ester is present in an amount of less than 15 wt%, preferably less than 10 wt%, more preferably less than 5 wt%.

25. A candle wax composition according to Claim 23 or 24, wherein the partial polyol ester is selected from monoglycerides, diglycerides or combinations thereof.

26. A candle wax composition according to Claim 25, wherein the partial polyol ester is selected from a monoglyceride.

27. A candle wax composition according to Claim 25 or 26, wherein the partial polyol ester is selected from glycerol, alkylene glycols such as ethylene glycol, diethylene glycol, triethylene glycol and neo-pentylglycol, pentaerythritol, trimethylolethane, trimethylolpropane, sorbitan, sorbitol, alicyclic polyols such as cyclohexanediols and inositol, and natural cyclic polyols such as glucose, galactose and sorbose.

28. A candle wax composition according to any preceding claim, wherein the composition further comprises at least one additive selected from the groupconsisting of: coloring agents, scenting agents, surfactants, emulsifiers and combinations thereof.

29. A candle wax composition according to Claim 28, wherein the at least one additive is present in an amount of 0.1 to 10 wt% of the composition, preferably 0.1 to 5 wt% of the composition.

30. A candle wax composition according to any preceding claim, wherein the composition does not comprise an antifoaming agent.31 . A candle wax composition according to Claim 30, wherein the composition has an iodine value of from 15 to 60, preferably from 25 to 50.

32. A candle wax composition according to any preceding claim, wherein the composition has a melting point of from 35 to 65 °C, preferably from 40 to 60 °C.

33. A candle comprising: a. a solidified candle body; and b. a candlewick extending into the candle body, wherein the solidified candle body is formed from a candle wax composition as defined in any one of Claims 1 to 32.

34. A candle according to Claim 33, wherein the candle is arranged within a container, preferably the container is formed from a glass, metal, wood, ceramic or plastic material.

35. A method of producing a candle wax composition, wherein the method comprises the steps of:a. providing one or more lauric fats in an amount of from 10 to 90 wt% of the composition; b. providing a plant-based oil and / or a plant-based wax forming the remainder of the composition; c. heating the one or more lauric fats and plant-based oil / wax to a temperature of from 40 to 90°C to form a liquid composition; d. mixing the liquid composition of one or more lauric fats and plant-based oil / wax to form a homogenous composition; e. cooling the homogeneous composition to room temperature, wherein the composition comprises from 4 to 45 wt% lauric acid (C12:0) and from 0.1 to 20% myristic acid (C14:0) and has an iodine value of from 5 to 75.

36. A method according to Claim 35, wherein the one or more lauric fats and plantbased oil / wax are combined prior to heating to a temperature of 40 to 90°C.

37. A method according to Claim 35, wherein the one or more lauric fats and plantbased oil / wax are first heated to a temperature of 40 to 90°C before the respective liquid compositions are combined.

38. A method according to any one of Claims 35 to 37, wherein the one or more lauric fats and plant-based oil / wax are heated to a temperature of 50 to 85°C, preferably a temperature of 55 to 75 °C.

39. A method according to any one of Claims 35 to 38, wherein the step of mixing the liquid composition of one or more lauric fats and plant-based oil / wax proceeds for a period of from 1 minute to 15 hours, preferably from 10 minutes to 10 hours, more preferably from 30 minutes to 5 hours.

40. A method according to any one of Claims 35 to 39, wherein the step of cooling the homogenous composition to room temperature comprises ambient cooling or cooling the homogenous composition using fans, a cooling jacket or a temperature- controlled water bath.41 . A method according to any one of Claims 35 to 40, wherein the one or more lauric fats are as defined in any one of claims 5 to 11 .

42. A method according to any one of Claims 35 to 41 , wherein the plant-based oil and plant-based wax are as defined in Claims 12 and 13.

43. A method according to any one of Claims 35 to 42, wherein the composition has a solid fat content (SFC) as defined in any one of Claims 14 to 19.

44. A method according to any one of Claims 35 to 43, wherein the method further comprises the step of providing a paraffin wax, preferably in an amount of from 30 to 45 wt% of the composition, prior to heating to a temperature of from 40 to 90 °C.

45. A method according to any one of Claims 35 to 44, wherein the method further comprises the step of providing one or more polyol fatty acid or partial polyol ester as defined in any one of claims 23 to 27, prior to heating to a temperature of from 40 to 90 °C .

46. Use of a candle wax composition according to any one of claims 1 to 32, for reducing the formation of frosting.

47. Use of a candle wax composition according to any one of claims 1 to 32, for improving the adhesion of candlewax to glass.

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