Method for manufacturing aromatherapy candle

Abstract

A method of making an aromatherapy candle is disclosed wherein the candle comprises a wax or gel body, at least one wick, and a perfume or perfume composition contained in the wax or gel body. The method comprises providing a wax or gel for forming a wax or gel body, providing a fragrance or fragrance composition to be added to the wax or gel, providing at least one candlewick to be embedded in the wax or gel body wherein the candlewick partially protrudes from the wax or gel body so as to be able to ignite, and combining the wax or gel with the perfume or perfume composition and at least one candlewick to form the aromatherapy candle. The provision of the perfume or perfume composition comprises the intentional selection of the perfume or perfume composition based on its flash point and / or ethanol content, wherein the flash point is at least 82.5 DEG C. The lactone content of the perfume or perfume composition is preferably at most 1.7% by weight if the ethanol content is higher than 18% by weight.

Description

[0001] The invention relates to a method for manufacturing an aromatherapy candle.

[0002] Candles are very popular with consumers, especially in the home. In particular, scented candles (containing one or more essential oils mixed in wax) add an elegant ambience to a bedroom, living room or bathroom by releasing a pleasant aroma. Scented candles can create an atmosphere of health and well-being.

[0003] Unlike incense burners, scented candles do not add smoke to the air.

[0004] However, scented candles have been found to release potentially harmful chemicals such as formaldehyde, benzene and / or naphthalene.

[0005] It is an object of the present invention to provide a method for manufacturing a scented candle having low emission properties, in particular with regard to minimizing the levels of formaldehyde, benzene and / or naphthalene produced during the combustion process.

[0006] This object is achieved by a method for producing a scented candle, the candle comprising a wax or gel, at least one wick and a fragrance or fragrance composition contained in the wax or gel, wherein the method comprises:

[0007] a) providing a wax or gel for forming a wax or gel body,

[0008] b) providing a fragrance or fragrance composition to be added to the wax or gel,

[0009] c) providing at least one wick to be embedded in the wax or gel body, wherein the wick partially protrudes from the wax or gel body to enable ignition, and

[0010] d) combining the wax or gel with a fragrance or fragrance composition and at least one wick to form a scented candle.

[0011] In such methods, the provision of the flavor or flavor composition in step b) comprises intentionally selecting the flavor or flavor composition based on its flash point (wherein the flash point is at least 82.5° C.) and / or its ethanol content.

[0012] Flash point refers to the temperature at which a fragrance becomes flammable or ignitable when exposed to an open flame or spark. This is a characteristic commonly mentioned when selling fragrances or fragrance compositions on the market.

[0013] When analyzing approximately 160 data points associated with existing scented candles (various wax compositions, including various fragrances or fragrance compositions) and the corresponding fragrance flash points associated with the fragrances or fragrance compositions used in the candles, the inventors found that emission levels (e.g., formaldehyde and benzene) correlated with the fragrance flash point: the higher the fragrance flash point, the lower the corresponding emissions. Through analysis of the data points, they found that when scented candles use fragrances or fragrance compositions with fragrance flash points above 82.5°C, they successfully pass the formaldehyde maximum emission target (e.g., 30 μg / (m 3 )) and maximum emission targets for benzene (e.g. 0.17 μg / m 3 / day) with a probability of about 99%.

[0014] When analyzing about 160 data points, it was also found that the ethanol content of the fragrance or fragrance composition was also correlated with the candle passing the emissions test: if the ethanol content was at most 18% by weight, the probability of passing the emissions test was about 84% or more. If the ethanol content was above 18% by weight and the lactone content in the fragrance or fragrance composition was at most 1.7% by weight, the probability of the candle passing the emissions test was still high, reaching more than 70%.

[0015] Figure 1 and Figure 2 The measurement results of formaldehyde and benzene emissions of the above 160 samples are shown:

[0016] Figure 1 shows the formaldehyde emissions, and

[0017] Figure 2 Benzene emissions are shown.

[0018] Figure 3 The correlation between the ethanol content in a fragrance or fragrance composition and the probability of a candle passing an emissions test is shown.

[0019] Figure 1 Many small solid circles are shown in the figure, each representing a tested candle, showing the corresponding formaldehyde emission (vertical axis) and the relevant fragrance flash point (horizontal axis). It can be seen that the fragrance flash point > 82.5℃ will cause the formaldehyde emission of most candles to be lower than the target level, such as 30 μg / (unit m 3 "STPC" stands for "Single Time Point Concentration" and is related to the EN16739 standard. The inventors chose the latter because it appears to have the most stringent acceptable / maximum level of formaldehyde, setting a maximum value of 30 μg / (m 3 ). The measured formaldehyde concentrations represent the formaldehyde concentration after one hour of combustion in a "European standard room" ("unit") with a volume of 30 m3 and an air exchange rate of 0.5 / h.

[0020] Figure 2 Many small solid circles are shown in the figure, each representing a tested candle, showing the corresponding benzene emissions (vertical axis) and the relevant fragrance flash point (horizontal axis). It can be seen that fragrance flash point > 82.5℃ will cause the benzene emissions of most candles to be below the target level, for example 0.17 μg / m 3 / day. "TWA" stands for "time weighted average" and is related to the WHO guidelines on acceptable or maximum levels of benzene. The inventors chose the latter because it appears to be the most stringent with regard to the acceptable / maximum level of benzene, setting the maximum value of benzene at 0.17 micrograms / m 3 / day. The “time-weighted average” is the expected average value of burning a candle (corresponding sample) in a “European standard room” based on the most adverse exposure scenario for scented candles; here: 4 hours of burning time per 24 hours and 4 times of use per 7 days.

[0021] Without wishing to be bound by theory, the inventors believe that the shown correlation between the flash point of the fragrance and the emission levels of formaldehyde and benzene is related to combustion kinetics, with more complete combustion being associated with higher fragrance flash points, e.g. less formation of CH2O (formaldehyde) and / or C6H6 (benzene) which could be considered as potentially hazardous (intermediate) combustion products.

[0022] In the context of the present invention, deliberate selection of a fragrance or fragrance composition based on its flash point would include designing a fragrance or fragrance composition, or blending fragrance oils to arrive at a mixture, such that it meets specified flash point value requirements.

[0023] In a preferred embodiment, such fragrances or fragrance compositions are intentionally selected to have a flash point of at least 87.5°C, more preferably at least 95°C. In such an embodiment, the probability of the scented candle meeting the emission target is further increased. In particular, when the fragrance has a flash point of at least 95°C, the probability of achieving the emission target is about 100%.

[0024] In a second embodiment, the present invention also includes a scented candle made according to any of the above methods.

[0025] In one embodiment, the fragrance or fragrance composition of the scented candle accounts for 1% to 10% by weight of the wax or gel, preferably 4% to 6% by weight, and most preferably 2% to 4% by weight. Based on the findings of the aforementioned inventors, a wider range of fragrance loadings can be selected without violating emission targets. In particular, higher fragrance loadings (e.g., above 6% by weight) can be achieved, which can, for example, further improve the consumer's experience of using such a candle without causing the candle to produce harmful emissions.

[0026] In another embodiment, the flavor or flavor composition is intentionally selected based on its ethanol content.

[0027] from Figure 3 As can be seen from the sample of about 160 data points, when the ethanol content of the fragrance or fragrance composition is at most 18% by weight, about 84% of the candles passed the emission test. The data points with SHAP values ​​(horizontal axis) below 0.00 in the figure correspond to candles that failed the emission test.

[0028] In a further embodiment, the scented candle comprises more than one wick, preferably two, three or four. Increasing the number of wicks can result in an impressive candle burning aesthetic, supporting the creativity of candle manufacturers / designers and broadening the consumer experience. Increasing the number of (lit) wicks will also increase the emissions of the candle. However, such candles designed and manufactured according to the method of the present invention will still produce low emissions and can pass maximum emission targets (e.g., for formaldehyde and benzene).

[0029] Preferably, the formaldehyde emission of the scented candle manufactured according to the method of the present invention is less than 30 μg / (m 3 ), and / or the benzene emission of the scented candle manufactured according to the method of the present invention is less than 0.17 μg / m 3 / sky.

[0030] The present invention can be summarized as follows:

[0031] A method for making a scented candle, wherein the candle comprises a wax or gel, at least one wick, and a fragrance or fragrance composition contained in the wax or gel. The method comprises:

[0032] a) providing a wax or gel for forming a wax or gel body,

[0033] b) providing a fragrance or fragrance composition to be added to the wax or gel,

[0034] c) providing at least one wick to be embedded in the wax or gel body, wherein the wick partially protrudes from the wax or gel body to enable ignition, and

[0035] d) combining the wax or gel with a fragrance or fragrance composition and at least one wick to form a scented candle.

[0036] The provision of the fragrance or fragrance composition in step b) comprises intentionally selecting the fragrance or fragrance composition based on its flash point (wherein the flash point is at least 82.5° C.) and / or its ethanol content (preferably at most 18 wt %).

[0037] If the ethanol content is above 18% by weight, the lactone content of the fragrance or fragrance composition is preferably at most 1.7% by weight.

Claims

1. A method for making a scented candle, the candle comprising a wax or gel, at least one wick, and a fragrance or fragrance composition contained in the wax or gel, the method comprising: a) providing a wax or gel for forming the wax or gel body, b) providing a fragrance or fragrance composition to be added to the wax or gel, c) providing at least one wick to be embedded in the wax or gel body, wherein the wick partially protrudes from the wax or gel body to enable ignition, and d) combining the wax or gel with the fragrance or fragrance composition and at least one wick to form a scented candle, It is characterized in that The provision of the fragrance or fragrance composition in step b) comprises selecting the fragrance or fragrance composition based on: i) its flash point, wherein the flash point is at least 82.5°C, and / or ii) Its ethanol content.

2. The method according to claim 1, wherein: The flash point is at least 87.5°C, preferably at least 95°C.

3. The method according to claim 1 or 2, wherein: The ethanol content is at most 18% by weight.

4. The method according to claim 1 or 2, wherein: The ethanol content is higher than 18% by weight and the lactone content of the fragrance or fragrance composition is at most 1.7% by weight.

5. A scented candle manufactured according to the method according to any one of claims 1 to 4.

6. The scented candle according to claim 5, wherein: The fragrance or fragrance composition comprises 1 to 10 wt %, preferably 4 to 6 wt %, most preferably 2 to 4 wt % of the wax or gel.

7. The scented candle according to claim 5 or 6, wherein: The scented candle comprises more than one wick, preferably two, three or four wicks.

8. The scented candle according to any one of claims 5 to 7, wherein: The formaldehyde emission of the scented candle is less than 30 micrograms / (m 3 ), the emissions are measured according to EN16739.

9. The scented candle according to any one of claims 5 to 8, wherein: The benzene emission of the scented candle is less than 0.17 μg / m 3 / day, the emissions are determined based on the WHO's benzene emission guidelines with a lifetime risk of 1 / 1000000 scenario.

10. The scented candle according to claims 8 and 9, wherein: The formaldehyde emission is less than 30 micrograms / (unit: m 3 ), and the benzene emission is less than 0.17 μg / m 3 / sky.

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