Natural wax formulations with improved release properties

Abstract

The present disclosure relates to natural wax formulations and candles made therefrom having improved release properties from containers.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Application No. 63 / 353,656, filed on June 20, 2022, and European Application No. 22187085.0, filed on July 26, 2022. The entire contents of these applications are expressly incorporated herein by this reference. Technical Field

[0003] The present disclosure relates to wax formulations, typically natural wax formulations, and candles containing the wax formulations and having improved release properties from containers. Background Art

[0004] In modern times, candles have gained popularity for their aesthetic value and their ability to release a pleasant scent into the air when burning. They can be used to create a pleasant atmosphere, such as a soft, warm and / or romantic ambience, or simply to illuminate a dark space, often during a power outage.

[0005] At the same time, sustainability and eco-friendliness have become important in many industries, such as the candle industry. The transition from petroleum-based carbon to naturally sourced carbon has always been of interest to consumers, as using natural materials can reduce carbon footprints. Candles made from renewable resources and biodegradable continue the environmental culture of the industry and consumers. In some cases, certain natural waxes have additional benefits. For example, the use of soy wax can promote the development of the agricultural industry when consumers choose to purchase candles that use renewable soy resources. In another example, the use of beeswax is a way to support the environment because it can promote the growth of honey bee populations needed to pollinate food crops.

[0006] Upcycling or reusing containers used in candles is also another way to promote sustainability and eco-friendliness by minimizing the dumping of used containers (usually glass containers) into the waste stream. However, removing burn residues from used candles is a concern. Post-burn residues of wax formulations that are formulated for use in containers, such as formulations used for votive candles, are often difficult to remove from the containers, where removal of the burn residues may be impossible or, even if possible, may result in injury to the user.

[0007] The National Candle Association says the main safety concern is injuries from consumers removing "wax residue" from containers of burned wax. Consumers may use sharp objects to pry the burned residue apart, which could result in injury or break the container.

[0008] Thus, there is a continuing need for wax formulations that promote sustainability and eco-friendliness and / or that make post-burn residues easier to remove from containers. Summary of the invention

[0009] The following aspects of the present disclosure are intended to address one or more of the above-mentioned problems.

[0010] In a first aspect, the present invention relates to a wax formulation comprising:

[0011] a) stearic acid,

[0012] b) natural waxes, and

[0013] c) Volatile active substances.

[0014] In a second aspect, the present disclosure is directed to a candle comprising the wax formulation described herein.

[0015] In a third aspect, the present disclosure relates to a method comprising:

[0016] i.) mixing stearic acid, a natural wax, and a volatile active material to form a wax formulation; and

[0017] ii.) making candles using the wax formulation,

[0018] The natural wax is present in the wax formulation in an amount sufficient to allow the wax formulation to separate from the inner surface of the container when the candle cools below the melting point of the wax formulation after combustion ceases. DETAILED DESCRIPTION

[0019] As used herein, the terms "a", "an" or "the" mean "one or more" or "at least one", unless otherwise specified.

[0020] Although compositions and methods are described in terms of "comprising," "containing," or "including" various components or steps, compositions and methods may also "consist essentially of" or "consist of" the various components, materials, and steps. As used herein, the term "consist essentially of" should be interpreted as including the listed components, materials, or steps and such additional components, materials, or steps that do not materially affect the basic and novel properties of the composition or method. In some embodiments, a composition "consisting essentially of" according to an embodiment of the present disclosure does not include any additional components or materials that change the basic and novel properties of the composition.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this specification belongs.

[0022] It should be understood that any numerical range described herein is intended to include all subranges contained therein. For example, a range of "1 to 10" is intended to include all subranges between the stated minimum value of 1 and the stated maximum value of 10; that is, having a minimum value equal to or greater than 1 and a maximum value equal to or less than 10. Since the disclosed numerical ranges are continuous, they include every value between the minimum and maximum values. Unless otherwise expressly stated, the various numerical ranges specified in this application are approximate.

[0023] As used herein, unless otherwise indicated, the term "about" or "approximately" refers to the acceptable error of a particular value determined by one skilled in the art, which depends in part on how the value is measured or determined. In certain embodiments, the term "about" or "approximately" refers to within 1, 2, 3, or 4 standard deviations. In certain embodiments, the term "about" or "approximately" refers to within 50%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, or 0.05% of a given value or range.

[0024] Throughout this disclosure, various publications may be incorporated by reference. If the meaning of any term in these publications incorporated by reference conflicts with the meaning of the term in this disclosure, the meaning of the term in this disclosure takes precedence unless otherwise stated.

[0025] In a first aspect, the present invention relates to a wax formulation comprising:

[0026] a) stearic acid,

[0027] b) natural waxes, and

[0028] c) Volatile active substances.

[0029] In one embodiment, stearic acid is obtained from a natural source, typically a plant source, an animal source, or a combination thereof. In one embodiment, stearic acid is extracted from crude palm oil. In one embodiment, crude palm oil is fractionated into stearin / palm oil. In another embodiment, stearin / palm oil can be distilled into C 16-18 A fatty acid mixture of fatty acids, also known as triple pressed stearic acid. In one embodiment, the ratio of palmitic acid to stearic acid is 60 / 40.

[0030] The amount of stearic acid is not particularly limited. However, in one embodiment, the stearic acid is present in an amount of 5% to 60% by weight of the formulation. In one embodiment, the stearic acid is present in an amount of 20% to 50% by weight of the formulation.

[0031] Natural waxes may be any substance of natural origin which is a plastic to brittle solid at ambient temperature. Such natural waxes are typically mixtures comprising hydrocarbons, fatty acid esters of fatty alcohols (also known as aliphatic esters), fatty acid esters of glycerol (also known as glycerides), fatty acids and / or fatty alcohols.

[0032] The ability of a wax formulation to detach from the inner surface of a container may be affected by a variety of factors, such as the recrystallization time of the wax formulation during the phase transition from liquid to solid, the specific gravity of the wax formulation, the composition of the wax formulation, the density of the wax formulation, the coefficient of expansion of the wax formulation, the surface tension of the wax formulation, the nature and extent of the intermolecular interaction between the wax formulation and the inner surface of the container, etc.

[0033] In some cases, natural waxes containing hydrocarbons and / or fatty acid esters of fatty alcohols (also referred to as aliphatic esters) have unique properties that are suitable for the expansion and contraction mechanisms required for wax formulations to be able to detach from the inner surface of a container. They are more likely to maintain good tensile strength and maintain their elasticity during the entire heating and cooling process. The volume change of the wax formulation during the heating and cooling stages changes, enough to make the wax formulation detach from the inner surface of the container when it is cooled below the formulation melting point after combustion stops. Therefore, in one embodiment, the natural wax comprises hydrocarbons and / or fatty acid esters of fatty alcohols. In another embodiment, the natural wax does not contain fatty acid esters of glycerol (also referred to as glycerides).

[0034] Suitable natural waxes include, but are not limited to, those selected from the group consisting of: plant-based waxes, typically carnauba wax, soy wax, jojoba wax, candelilla wax, rice bran wax, rapeseed wax, coconut wax, laurel wax, castor wax, palm wax, sumac wax, sunflower wax and bayberry wax; animal-based waxes, typically beeswax; and any combination thereof.

[0035] The wax formulation according to the present invention may comprise one natural wax or a blend of two or more natural waxes. In one embodiment, the wax formulation comprises two or more natural waxes.

[0036] In one embodiment, the wax formulation comprises two or more natural waxes, wherein at least one of the natural waxes is carnauba wax. In one embodiment, the wax formulation comprises carnauba wax and a natural wax selected from the group consisting of soy wax, jojoba wax, candelilla wax, rice bran wax, rapeseed wax, coconut wax, laurel wax, castor wax, palm wax, sumac wax, sunflower wax, and bayberry wax; an animal-based wax, typically beeswax; and any combination thereof.

[0037] The amount of natural wax is not particularly limited. However, in one embodiment, the natural wax is present in an amount of 50% to 95% by weight of the wax formulation. In one embodiment, the natural wax is present in an amount of 50% to 90% by weight of the wax formulation, typically 50% to 85%, more typically 50% to 80%. In one embodiment, the natural wax is present in an amount of 50% to 75% by weight of the wax formulation, typically 50% to 70%, more typically 50% to 65%, more typically 50% to 60%. In one embodiment, the natural wax is present in an amount of 50% to 55% by weight of the wax formulation.

[0038] In one embodiment, when the wax formulation comprises two or more natural waxes, wherein at least one of the natural waxes is carnauba wax, the carnauba wax is present in an amount of 1% to 20%, typically 2% to 15%, more typically 2% to 10%.

[0039] Without wishing to be bound by theory, it is believed that the presence of carnauba wax with a natural wax selected from the group consisting of soy wax, jojoba wax, candelilla wax, rice bran wax, rapeseed wax, coconut wax, laurel wax, castor wax, palm wax, sumac wax, sunflower wax and bayberry wax; an animal-based wax, typically beeswax; and any combination thereof, enhances the crystallinity of the natural wax and results in an improved release ability of the wax formulation from the inner surface of the container surface.

[0040] The wax formulation according to the present disclosure may optionally contain one or more synthetic waxes. Suitable synthetic waxes include, but are not limited to, paraffin wax, microcrystalline wax, and the like.

[0041] The wax formulations according to the present disclosure may optionally contain polyethylene. The polyethylene may be used to aid in the ability of the wax formulation to detach from the inner surface of the container when it cools below the melting point of the formulation after combustion has ceased. In one embodiment, the molecular weight of the polyethylene is from 300 to 2500. In one embodiment, the melting point of the polyethylene is from 80 to 160 degrees Celsius. An exemplary polyethylene is a fully saturated ethylene homopolymer having a melting point of 88°C, which is sold under the trade name POLYWAX 500. In one embodiment, the polyethylene is present in an amount of 0.05% to 5% by weight of the formulation.

[0042] The wax formulation according to the present disclosure may optionally contain a linear alcohol. The linear alcohol can improve the dispersibility of the volatile active substance by destroying the crystal stacking of the wax formulation and opening the gaps between the wax crystals, thereby allowing the volatile active substance to evenly penetrate between the wax crystals. Exemplary linear alcohols include, but are not limited to, those sold under the trade name UNILIN TM High molecular weight linear primary alcohols for sale, such as UNILIN TM 550、UNILIN TM 700 and UNILIN TM1000. In one embodiment, the linear alcohol is present in an amount of 0.1% to 0.6% w / w of the wax formulation.

[0043] The wax formulation may also include additional optional ingredients to provide enhanced or additional aesthetic and / or functional improvements. Specifically, additional materials that may be included in the wax formulation include colorants, decorative materials, solvents, stabilizers, antioxidants, and ultraviolet blockers. Such optional ingredients do not warrant a more detailed description here, which is in any case not exhaustive. The technician is able to select them based on his general knowledge and the desired properties of the candle. Specifically, the type and amount of additional ingredients should be selected from ingredients that do not change the structure or combustion performance of the wax formulation.

[0044] The volatile active substance can be any type of volatile active substance. In some embodiments, it is a fragrance, a malodor counteractant, an antibacterial agent, an insect repellent, or any combination thereof. In one embodiment, the volatile active substance is a fragrance.

[0045] As used herein, the term "fragrance" refers to any perfuming ingredient or mixture thereof. As used herein, "perfuming ingredient" refers to compounds currently used in the perfumery industry, i.e. compounds used as active ingredients in scented candles to impart a pleasant effect to their surroundings. In other words, for such an ingredient or mixture to be considered a perfuming agent, it must be recognized by those skilled in the art of perfumery as being able to impart or modify the scent of a candle in an active or pleasant manner, rather than merely possessing a scent. Furthermore, the definition is also intended to include compounds that do not necessarily possess a scent, but are able to modulate the scent of a perfumed composition and thus alter the user's perception of the scent of such a composition.

[0046] The nature and type of these flavoring ingredients do not guarantee to be described in more detail here, and they are all impossible to be exhaustive in any case, and the technician can select them based on their general knowledge and according to expected use or application and required sensory effect. Generally speaking, these flavoring ingredients belong to different chemical categories, such as alcohols, aldehydes, ketones, esters, ethers, acetates, nitriles, terpenoids, nitrogen-containing or sulfur-containing heterocyclic compounds and essential oils, and the flavoring ingredients can be natural or synthetic sources. In any case, many of these ingredients are listed in references such as S.Arctander's work Perfume and Flavor Chemicals, 1969, Montclair, New Jersey, USA or its updated version or other works of similar nature, and in the patent literature abundant in the field of spices. It should also be understood that the composition can also be a compound known to release various types of flavoring compounds in a controlled manner.

[0047] The term "malodor counteractant" or "malodor counteracting ingredient" refers to a compound that is capable of reducing the perception of malodor (i.e., an unpleasant or offensive odor to the human nose) by counteracting and / or masking the malodor. In some cases, malodor counteractants have the ability to react with key compounds that cause known malodors. These reactions result in a reduction in the airborne levels of the malodorous material, thereby reducing the perception of the malodor. Such malodor counteractants are known to those skilled in the art.

[0048] Suitable insect repellents include, but are not limited to, citronella oil, dimethyl phthalate, and n,n-dimethyl-m-toluamide.

[0049] The amount of volatile active material is not particularly limited. However, in one embodiment, the volatile active material is typically present in the candle in an amount of 10 to 25 weight percent based on the total weight of the composition.

[0050] In a second aspect, the present disclosure is directed to a candle comprising the wax formulation described herein.

[0051] In one embodiment, the candle further comprises a container, wherein the candle is located within the container.

[0052] As described herein, the amount of natural wax in the wax formulation is not particularly limited. However, in candles according to the present invention, the amount of natural wax sufficient to release the wax formulation from the inner surface of the container is 50% to 95% by weight of the wax formulation.

[0053] The wax formulation of the candle is solid at room temperature, and when at least one candle burns, a portion of the wax formulation undergoes a phase transition from solid to liquid, and the temperature of the at least one candle increases to above the melting point of the wax formulation, wherein when the at least one candle cools to below the melting point of the wax formulation after combustion ceases, the liquid portion of the wax formulation undergoes a phase transition from liquid to solid, wherein the amount of natural wax present in the wax formulation is sufficient to enable the wax formulation to detach from the inner surface of the container when the candle cools to below the melting point of the wax formulation after combustion ceases.

[0054] In a third aspect, the present invention relates to a method comprising:

[0055] i.) mixing stearic acid, a natural wax, and a volatile active material to form a wax formulation; and

[0056] ii.) making candles using the wax formulation,

[0057] The natural wax is present in the wax formulation in an amount sufficient to allow the wax formulation to separate from the inner surface of the container when the candle cools below the melting point of the wax formulation after combustion ceases.

[0058] In general, known candle manufacturing methods can be used to provide candles disclosed herein. In some cases, a wick coated with a high melting point wax is cut to a desired length and then crimped onto a small metal wick holder. The wick holder is attached to the bottom of the container. At the top of the container, a metal wick guide is placed to keep the wick vertical. A wax formulation formed by mixing stearic acid, natural wax, and a volatile active substance is poured into the container to a desired level. The candle is cooled to room temperature and then the metal wick guide is removed. Alternatively, an accelerated cooling process can be used. The wick is trimmed to a suitable length to produce a finished candle. Other methods can be used, including methods common in the industry.

[0059] The formulations, products, uses and methods according to the present disclosure are further illustrated by the following non-limiting examples.

[0060] Example 1. Wax formulation of the present invention

[0061] Table 1.

[0062] Element Amount (weight percentage of wax formulation) Soy wax 45 Carnauba wax 10 Triple Pressed Stearic Acid 39.5 Fragrance 5.5

[0063] Table 2.

[0064] Element Amount (weight percentage of wax formulation) Rapeseed wax 45 Carnauba wax 10 Triple Pressed Stearic Acid 39.5 Fragrance 5.5

[0065] Table 3.

[0066] Element Amount (weight percentage of wax formulation) Soy wax 45.0 Castor wax 3.6 Carnauba wax 5.4 Triple Pressed Stearic Acid 36.0 Fragrance 10.0

[0067] Table 4.

[0068] Element Amount (weight percentage of wax formulation) Soy wax 40.5 Castor wax 5.4 Carnauba wax 3.6 Triple Pressed Stearic Acid 40.5 Fragrance 10.0

[0069] The disclosed subject matter has been described with reference to specific details of particular embodiments. Unless such details are included in the appended claims, such details should not be construed as limitations on the scope of the disclosed subject matter.

[0070] Therefore, the exemplary embodiments described herein are well suited for achieving the objects and advantages described and those inherent therein. The specific embodiments disclosed above are illustrative only, as the exemplary embodiments described herein may be modified and practiced in different but equivalent manners, which will be apparent to those of ordinary skill in the art having the benefit of the teachings herein. In addition, the details of construction or design shown herein are not subject to any limitations except as described in the following claims. Therefore, it is apparent that the specific illustrative embodiments disclosed above may be changed, combined or modified, and all such variations are considered to be within the scope and spirit of the exemplary embodiments described herein. The exemplary embodiments described herein, which are illustratively disclosed herein, may be appropriately practiced in the absence of any elements not specifically disclosed herein and / or any optional elements disclosed herein.

Claims

1. A wax formulation comprising: a) stearic acid, b) natural waxes, and c) Volatile active substances.

2. The wax formulation according to claim 1, wherein the stearic acid is present in an amount of 5% to 60%, typically 20% to 50% by weight of the wax formulation.

3. The wax formulation according to claim 1 or 2, wherein the stearic acid is obtained from a natural source.

4. The wax formulation according to any one of claims 1 to 3, wherein the natural wax is selected from the group consisting of plant-based waxes, typically carnauba wax, soy wax, jojoba wax, candelilla wax, rice wax, rapeseed wax, coconut wax, laurel wax, castor wax, palm wax, sumac wax, sunflower wax and bayberry wax; animal-based wax, typically beeswax; and any combination thereof.

5. The wax formulation according to any one of claims 1 to 4, wherein the wax formulation comprises two or more natural waxes.

6. The wax formulation according to any one of claims 1 to 5, wherein the natural wax comprises hydrocarbons, and / or fatty acid esters of fatty alcohols.

7. The wax formulation according to any one of claims 1 to 6, wherein the natural wax is present in an amount of 50% to 95% by weight of the wax formulation.

8. The wax formulation according to any one of claims 1 to 7, further comprising a synthetic wax, typically selected from the group consisting of paraffin wax, microcrystalline wax or a combination thereof.

9. The wax formulation according to any one of claims 1 to 8, further comprising polyethylene, typically present in an amount of 0.05% to 5% by weight of the wax formulation.

10. The wax formulation according to any one of claims 1 to 9, further comprising a linear alcohol, typically present in an amount of 0.1% to 0.6% by weight of the wax formulation.

11. A candle comprising the wax formulation of any one of claims 1 to 10.

12. The candle of claim 11 further comprising a container, wherein the candle is located within the container.

13. The candle of claim 11 or 12, wherein the wax formulation is solid at room temperature, and when at least one candle burns, a portion of the wax formulation undergoes a phase transition from solid to liquid, and the temperature of the at least one candle increases to above the melting point of the wax formulation, wherein when the at least one candle cools below the melting point of the wax formulation after combustion ceases, the liquid portion of the wax formulation undergoes a phase transition from liquid to solid, wherein the natural wax is present in the wax formulation in an amount sufficient to enable the wax formulation to detach from the inner surface of the container when the candle cools below the melting point of the wax formulation after combustion ceases.

14. The candle of any one of claims 11 to 13, wherein the amount of natural wax sufficient to lift the wax formulation off the inner surface of the container is from 50% to 95% by weight of the wax formulation.

15. A method comprising: i.) mixing stearic acid, natural wax and volatile active material to form a wax formulation; and ii.) making candles using the wax formulation, The natural wax is present in the wax formulation in an amount sufficient to allow the wax formulation to separate from the inner surface of the container when the candle cools below the melting point of the wax formulation after combustion ceases.

16. The method of claim 15, wherein the amount of natural wax sufficient to release the wax formulation from the inner surface of the container is 50% to 95% by weight of the wax formulation.