Non-sooting containerized candle

FIELD OF INVENTION

The present invention relates to a non-sooting containerized candle. More particularly, the invention relates to a candle container having a pattern of holes in the upper wall portion of the container for venting the container so as to control air flow into and out of the container to provide complete combustion of the candle in the container and prevent sooting or the emission of carbon particulates.

BACKGROUND OF INVENTION

Various types of candles are known. However, many types of candles are not able to be properly controlled during burning thereof and, thus, do not provide complete combustion. These candles may be burned by using a wick and/or in combination with a fuel. The products of complete combustion are water and carbon dioxide. When combustion is not complete, carbon particulates are also generated or emitted and deposited on a wall of a container for the candle or on a surface of the surrounding environment. These carbon particulates are commonly referred to as soot. Generally, consumers do not want to use candles that emit soot into the environment or onto surrounding surfaces. Accordingly, non-sooting candles are desirable.

U.S. Pat. No. 6,029,650 describes a personal heating device including a tubular chamber with air intake holes formed in the chamber approximate the closed end to allow air to enter the chamber, and vent holes formed in the opposing open end to allow air and combustion gases to exit the chamber. A cap covers the chamber's open end to hold in heat and regulate air exiting the vent holes. The heat source in the chamber is a candle.

U.S. Pat. No. 4,781,895 describes a candle-powered aroma generator in lantern format for a scentless candle and replaceable fragrance-containing cartridge heated by the candle. The generator includes a housing with hollow base having a circumferential array of vent holes therein. Seated on the base is a cylindrical shell with a removable metal cover with a lower apron. The apron contains a series of vent holes therein. The roof of the cover includes a removable cap with an array of vent holes therein. Scented vapors from a cartridge are discharged through the top center vent holes. Due to vent holes 11 and 16, the container acts as a chimney to create a continuous upward flow of air to promote burning of the candle.

U.S. Pat. No. 1,388,267 describes a lantern with a plate, chimney, candle in a container, and hood or canopy. Openings are provided in the upper half of the chimney to supply air necessary to support combustion.

U.S. Pat. No. 1,295,679 describes a tubular member for placement over a candle. The tubular member is perforated throughout its length to provide for admission of air to the flame and permit escape of rays of light.

U.S. Pat. Nos. 6,382,962 B1 and 6,663,384 B2 describe a venting cover for a containerized candle which is said to improve combustion and eliminate candle smoke. The cover is preferably made of metal and includes a central exhaust vent positioned directly above the flame and oblong inlet vents positioned adjacent to the rim of the cover. The cross-sectional area of the exhaust vent and the aggregate cross-sectional area of the inlet vents are said to be approximately equal and are said to provide a concentric laminar air flow within the interior of the jar. This is said to stabilize the flame and improve the efficiency of the combustion.

U.S. Reissue Pat. No. Re. 20,434 describes a candle and fixture therefore which allows the candle to burn down without soiling the fixture. The fixture includes a draft regulating cap set upon the upper end of a glass tube. The cap includes registering air supply holes which are adjustable for adjusting the air supply. The center opening is an outlet for hot gaseous products of combustion of the candle flame. The draft created by the upward flow of the combustion gases draws outside air down through openings where this cold air is deflected by a flange and directed down through the interior of a film to the base of the flame. The adjustment in registry of openings serve to control the magnitude of the flame and thereby the intensity of the light of the flame and duration of the candle.

U.S. Pat. No. 3,942,940 describes a candle in an unbreakable container. The container includes a plurality of openings or cut-outs in the container side wall to provide for the passage of light. Preferably, four cut-outs are provided at 90° intervals around the side wall.

U.S. Pat. No. 5,683,239 describes a candle holder with a spring-loaded cover. The holder includes a housing with a heat shield positioned inside thereof. The heat shield has a plurality of holes (which can be of any shape) arranged in a desired pattern to enhance the aesthetic effect of the lit candle. A cover with through-holes is present on top of the housing. Channels in the base of the holder and also in the cover of the holder provide air passages for air to pass into and out of the housing.

U.S. Pat. No. 2,072,692 describes a candle and cover member including a series of openings. These openings are spaced in the cover member at a higher level than the candle flame for the purpose of permitting air to enter and feed the candle flame for combustion purposes. Another opening is present at the top of the cover. When the candle is burning, the combustion products escape through a tube in the cover into space present in the walls of the cover's canopy for exhaust into the outer air.

U.S. Pat. No. 2,001,312 describes a container for a candle having an outer translucent shell and a liner. The liner has perforations cut therein to provide a design allowing the candle light to be visible therethrough.

U.S. Pat. Nos. 6,589,047 B1 and 6,585,510 B2 describe venting plates for the top openings of containerized candles. The venting plates provide for soot-free combustion. The venting plates include a flat disc-shaped top and a channeled annular baffle. The plate sits atop the candle vessel so as to allow the flow of inlet air underneath the venting plate between the plate top and the brim of the candle vessel. The baffle redirects inlet air flow and funnels it into distinct columns culminating in increased velocity of the air flow down the vessel side walls. The increased flow moves the melted wax pool towards the flame promoting improved scent distribution.

U.S. Patent Application Publication No. 2005/0277078 A1 describes a venting chassis for a containerized candle. The venting chassis sits atop a candle vessel and permits inlet air flow underneath the venting chassis. The chassis includes a skirt which physically separates inlet air from exhaust air flow to facilitate laminar air flow within the containerized candle. The skirt constrains the inlet air flow to increase the velocity and inertia of the air flow. The venting chassis is stated to reduce turbulence within the jar interior and stabilize the flame, which leads to a cleaner combustion process and reduced carbon residue (smoke) in the exhaust.

U.S. Pat. No. 6,231,336 B1 describes a shade structure for a candle. The candle structure consists of a container body for containing a candle, a shade body attached to the container and a rotatable covering plate. The shade body includes a central exhaust air hole, a plurality of apertures along the top of the circumferential edge of the shade body to allow convection flow of air into the container body, and a plurality of auxiliary openings. The rotating covering plate is provided with a plurality of holes which can be rotatably adjusted to correspond to the auxiliary openings of the shade body by rotating the covering plate with respect to the shade body. The covering plate is rotated to adjust for the room temperature to provide better burning characteristic for the candle.

U.S. Pat. No. 7,226,284 B2 describes a method and apparatus for controlling a candle flame. The candle flame is provided in a controllable environment, which is described as an enclosed area formed at least in part by an air-tight cover. Air is forced into the enclosed area by an air movement device, e.g., a fan, to keep the flame burning. The flame is extinguished by reducing, e.g., stopping, air flow into the enclosed area.

These devices have various shortcomings. These and other shortcomings of the devices are addressed by the present invention.

SUMMARY OF THE INVENTION

The present invention relates to a non-sooting containerized candle. More particularly, the invention relates to an open-topped candle container having a pattern of holes in the upper wall portion of the container for venting the container so as to control air flow into and out of the container to provide complete combustion of the candle in the container and prevent emission of carbon particulates, commonly known as soot. A good burning candle, whether scented or unscented, is provided when fuel consumption is controlled and combustion is complete. When combustion is not complete, carbon particulates, along with water and carbon dioxide, which are the products of complete combustion, are also generated or emitted and deposited on the container wall and/or on a surface in the surrounding environment.

The pattern of holes in a container of the invention may be varied and are such so as to provide venting of the candle containers by controlling or adjusting air flow from a turbulent air flow to a laminar air flow while the candle is burning. Laminar air flow prevents the candle flame from flickering which in turn results in complete combustion and a clean or non-sooting burning candle. More particularly, laminar air flow occurs when a fluid flows in parallel layers, with no disruption between the layers. Laminar air flow is a flow regime characterized by high momentum diffusion, low momentum convection and pressure and velocity independent from time. Accordingly, laminar air flow is “smooth”, which is the opposite of turbulent air flow which is “rough”. Particularly, turbulent air flow is a flow regime characterized by chaotic, stochastic property changes. This includes low momentum diffusion, high momentum convection and rapid variation of pressure and velocity in space and time.

Varying patterns of holes positioned in the upper wall portion or circumference of a candle container may be used in accordance with the invention. Size, shape and position of the holes making up the pattern can be adjusted based on the shape and size of the containerized candle. The size and position of the holes are such that the holes provide concentric laminar air flow within the container which stabilizes the flame and permits sufficient ambient air flow directly to the base of the flame. Preferred patterns of holes to be present in the upper wall circumference of a candle container are as follows:

(1) a single row of evenly spaced holes of a predetermined diameter;

(2) two offset rows of holes, a top row of evenly spaced holes of a first predetermined diameter and a bottom row of evenly spaced holes of a second predetermined diameter which is smaller than the first predetermined diameter;

(3) three rows of holes, top and bottom aligned rows of evenly spaced holes of a first predetermined diameter and a middle offset row of evenly spaced holes of a second predetermined diameter which is smaller than the first predetermined diameter;

(4) three aligned rows of holes, each row being of evenly spaced holes of a predetermined diameter;

(5) spaced groups of three rows of holes, each group having top and bottom aligned rows of four holes of a first predetermined diameter and a middle offset row of three holes of a second predetermined diameter which is smaller than the first predetermined diameter; and

(6) two rows of spaced groups of holes of a predetermined diameter, the groups of each row being of three rows including top and bottom aligned rows of two holes and a middle offset row of three holes.

While the above described patterns of holes are preferred, the holes may be in any suitable arrangement and of any suitable size so long as structured to provide a laminar air flow in relation to a container holding a burning candle.

The above and other aspects of the present invention will be apparent from the following description of the preferred embodiments of the invention and from the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Referring to the drawings:

FIG. 1 illustrates a perspective view of a first embodiment of the containerized candle of the invention.

FIG. 2 illustrates a top view of FIG. 1.

FIG. 3 illustrates a cross-sectional view of FIG. 1 showing air flow.

FIG. 4 illustrates a second embodiment of a containerized candle of the invention having a single row of evenly spaced approximately 7 mm diameter holes along an upper wall circumference of the candle container.

FIG. 5 illustrates the pattern of the holes of FIG. 4.

FIG. 6 illustrates a third embodiment of the containerized candle of the invention having two offset rows of holes, a top row of evenly spaced 7 mm diameter holes and a bottom row of evenly spaced 4 mm diameter holes.

FIG. 7 illustrates the pattern of the holes of FIG. 6.

FIG. 8 illustrates a fourth embodiment of the containerized candle of the invention having three rows of holes, top and bottom aligned rows of evenly spaced about 7 mm diameter holes and a middle offset row of evenly spaced about 4 mm diameter holes.

FIG. 9 illustrates the pattern of the holes of FIG. 8.

FIG. 10 illustrates a fifth embodiment of the containerized candle of the invention having three aligned rows of holes, each row being of evenly spaced about 4 mm diameter holes.

FIG. 11 illustrates the pattern of the holes of FIG. 10.

FIG. 12 illustrates a sixth embodiment of the containerized candle of the invention having spaced groups of three rows of holes, each group having top and bottom aligned rows of four holes of about 7 mm diameter and a middle offset row of three holes of about 4 mm diameter.

FIG. 13 illustrates the pattern of the holes of FIG. 12.

FIG. 14 illustrates a seventh embodiment of the containerized candle of the invention having two rows of spaced groups of about 4 mm diameter holes, the groups of each row being of three rows including top and bottom aligned rows of two holes and a middle offset row of three holes.

FIG. 15 illustrates the pattern of the holes of FIG. 14.

FIG. 16 shows the filters of Test Sample 1 and Test Sample 2 after burning.

FIG. 17 shows the filters of Test Sample 3 and Test Sample 4 after burning.

FIG. 18 shows the filters of Test Sample 5 and Test Sample 6 after burning.

FIG. 19 shows the filters of Test Sample 5, Test Sample 6 and Test Sample 7 after burning.

FIG. 20 illustrates the optical density measurements for Test Sample 1 through Test Sample 7 over time.

FIG. 21 illustrates the average, minimum and maximum temperature of vented jar side walls for Test Samples A-E.

FIG. 22 illustrates the average, minimum and maximum temperature of non-vented jar side walls for Test Samples F-J.

FIG. 23 illustrates samples of candles burned without a screen on the top opening.

FIG. 24 illustrates samples of candles burned with a screen on the top opening.

FIGS. 25-27 illustrate gravimetric specifications as utilized in measuring the Test Samples.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 1-27, the present invention relates to a non-sooting containerized candle 50. More particularly, the invention relates to candle containers 52 having a pattern of holes 54 in the upper side wall portion 56 of the container 52 for venting the container to provide complete combustion of the candle in the container and to prevent emission of carbon particulates. A clean or non-sooting candle, whether scented or unscented, has controlled fuel consumption and complete combustion. When combustion is not complete, carbon particulates, along with water and carbon dioxide, which are the products of complete combustion, are also generated or emitted and deposited as soot on the container wall and/or a surface in the surrounding environment. This generally is an undesirable result of burning a candle for users. The containerized candle of the present invention reduces soot emission and, as such, is a non-sooting candle.

The containerized candle 50 of the present invention preferably comprises (1) a jar or container 52 having at least one side wall 56, a top opening 68 and a plurality of holes 54 in an upper wall portion of the container, preferably adjacent the top peripheral edge 66 of the side wall(s) 56 of the container 52, (2) a wick 58 inside the container 52, (3) a sustainer 60 for securing the wick 58 to a base 62 of the container 52 and (4) a wax or other fuel composition 64 surrounding the lowermost part of the wick 58. The container 52 may be of any suitable shape, such as cylindrical, round, square, oval, pentagonal, hexagonal, octagonal, other geometrical designs or the like. The walls 56 of the container 52 may also be any suitable shape, such as substantially straight/vertical as to the base with a straight top peripheral edge, substantially curved with a curved top or upper peripheral edge, curved body with a base and opening proportionately balanced to be aesthetically pleasing, or the like. In one preferred embodiment, the top peripheral edge 66 is curved inward as shown in FIG. 1. However, the top peripheral edge 66 may be curved outward or in any other suitable directional arrangement.

A containerized candle 50 which is a rounded container with curved side walls and a curved top peripheral edge is shown for example in FIGS. 1-3. A containerized candle 50 which is cylindrical with substantially straight/vertical side walls and a straight or linear top peripheral edge is shown for example in FIGS. 4, 6, 8, 10, 12 and 14.

The patterns of holes 54 adjacent the top peripheral edge 66 of the upper portion of the side wall 56 of container 52 controls or adjusts air flow into and out of the container from a turbulent air flow to a laminar air flow when a candle in the container is burning. Laminar air flow prevents the candle flame from flickering which in turn results in complete combustion and a clean burning candle. More particularly, laminar air flow occurs when the air flows in parallel layers, with no disruption between the layers. Laminar air flow is a flow regime characterized by high momentum diffusion, low momentum convection and pressure and velocity independent from time. Accordingly, laminar air flow is “smooth”, which is the opposite of turbulent air flow which is “rough”. Turbulent air flow is a flow regime characterized by chaotic, stochastic property changes. This includes low momentum diffusion, high momentum convection and rapid variation of pressure and velocity in space and time. The laminar air flow in the containerized candles prevents the candle flame from flickering, resulting in complete combustion and a non-sooting candle.

The upper wall portion containing the pattern of holes is considered that portion above the mid-point of the height of the container and below the upper edge of the container defining the top opening in the container. Preferably, the pattern of holes is present in the area spaced about 5 mm to about 80 mm below the top edge of the container defining the top opening, more preferably about 10 mm to about 50 mm below the top edge of the container defining the top opening.

Various patterns of holes 54 for inclusion in the upper circumference 66 of the side wall 56 of a candle container 52 may be used in accordance with the invention. Size, shape and position of the pattern of holes can be adjusted based on the shape and size of the containerized candle. The size and position of the pattern of holes is such that it provides concentric laminar air flow within the container which stabilizes the flame and permits sufficient ambient air flow directly to the base of the flame. Preferred patterns of holes 54 include:

(1) a single row of evenly spaced holes of a predetermined diameter;

(4) three aligned rows of holes, each row being of evenly spaced holes of a predetermined diameter;

(6) two rows of spaced groups of holes having a predetermined diameter, the groups of each row being of three rows including top and bottom aligned rows of two holes and a middle offset row of three holes.

More preferably, the above six patterns of holes 54 include:

(1) a single row of evenly spaced approximately 7 millimeter (mm) diameter holes, as shown for example in FIGS. 1 and 2 for a curved wall container and FIGS. 4 and 5 for a straight wall container;

(2) two offset rows of holes, a top row of evenly spaced 7 mm diameter holes and a bottom row of evenly spaced 4 mm diameter holes, as shown for example in FIGS. 6 and 7;

(3) three rows of holes, top and bottom aligned rows of evenly spaced about 7 mm diameter holes and a middle offset row of evenly spaced about 4 mm diameter holes, as shown for example in FIGS. 8 and 9;

(4) three aligned rows of holes, each row being of evenly spaced about 4 mm diameter holes, as shown for example in FIGS. 10 and 11;

(5) spaced groups of three rows of holes, each group having top and bottom aligned rows of four holes of about 7 mm diameter and a middle offset row of three holes of about 4 mm diameter, as shown for example in FIGS. 12 and 13; and

(6) two rows of spaced groups of about 4 mm diameter holes, the groups of each row being of three rows including top and bottom aligned rows of two holes and a middle offset row of three holes, as shown for example in FIGS. 14 and 15.

While these patterns of holes are preferred, the holes may be in any suitable arrangement and in any suitable size and shape so long as structured to provide a laminar air flow in relation to a container holding a burning candle. Preferably individual holes will be in a diameter in a range of about 2 mm to about 20 mm. Preferably the combined openings provided by the pattern of holes will be in a range of about 50 mm to 1000 mm. The sizing of the holes can vary in proportion to the overall size of the container. For example, a container of a height of 6 cm and a diameter of 6.5 cm will preferably have holes in a range of about 80 mm to about 300 mm, whereas a container of a greater height of 10 cm and a diameter of 7 cm will preferably have holes in a range of about 300 mm to about 600 mm. Generally, the hole openings cover about 20% of the container height and/or are present in a ratio of 1:4 as to hole opening to closed side wall.

The flow of air in the candle container 52 is shown for example in FIG. 3. Particularly, air is drawn in through the holes 54 in the side wall 56 of the container 52 into the interior of the container 52 and out through the top opening 68 of the container 52 as shown by the arrows. This air flow is laminar air flow which prevents the candle flame from flickering which in turn results in complete combustion, and thus a clean burning, non-sooting candle.

The candles of the present invention may be fragranced or unfragranced candles which are burned in households to provide ambience, fragrance or elimination of odors. As set forth above, the natural products of candle combustion are water and carbon dioxide. The burning of candles may also produce other products, such as volatile organic compounds (VOCs) and particulates as detailed above, depending on how the candle is made. Due to environmental concerns and to illustrate the improvement obtained by the invention, the candles of the present invention were evaluated by the environmental testing organizations Air Quality Sciences (AQS) and TNO to quantify the candle emissions when providing laminar air flow in the containerized candle. Particulate (soot) emissions of the candles were measured using optical density measurement. Samples of candles were evaluated for VOC and soot emission (particulates) and the procedure for evaluating soot emission is detailed below.

Procedure

1) Quantification of Candle Soot Emission Using Optical Density Measurements

Emissions from candles are collected on a filter over a defined period of time. Optical density of each filter paper was measured at the end of each burn period. The same filter paper was used throughout the test to collect emissions cumulatively. The amount of emissions was quantified by measuring the light reflectance from the filter using an optical densitometer in the reflection mode. By dividing the measured optical density by the individual burn rate, a relative comparison can be made between candles for emission even when the candles burn at different rates.

2) Temperature Measurement of Side Wall and Bottom Temperature

Side wall temperature and bottom temperature of each candle was measured every four hours using a thermocouple board. A thermocouple board has four thermocouples for measuring side wall temperature and one thermocouple for measuring bottom temperature. The candles were marked in order to measure temperature at the same location throughout the experiment. The maximum allowable wall temperature was considered to be 150° F. (66° C.), due to the startle reflex (dropping of the candle) and pain tolerance index. Temperatures above 150° F. (66° C.) can cause potential skin damage or burn.

3) Burn Rate Measurement

The burn rate of each candle is calculated every four hours by weighing each sample before and after each burn period. The ideal burn rate for a 4 ounce container is 3 to 4 gram per hour; below 3 grams, the candle will have a small flame and a high retention; above 4 grams, the candle will have a big flame, sooty and a higher wall temperature.

4) Sampling

Five samples of each variant were used for evaluation of the following.

- a) Test Sample 1—Tender Flowers with a screen on top of a jar to modify air flow.
- b) Test Sample 2—Tender Flowers in a jar without a screen.
- c) Test Sample 3—Apple & Cinnamon with a screen on top of a jar to modify air flow.
- d) Test Sample 4—Apple & Cinnamon in a jar without a screen.
- e) Test Sample 5—Angel Whispers in a metal can with holes in the manner of the invention in the upper side wall of the container; five different hole patterns, as shown in FIGS. 4, 6, 8, 10 and 12, were evaluated for burn characteristics (burn rate, flame height, coking, wall temperature and blooming). Results using the five patterns were applied to configure holes of the containers tested for emission.
- f) Test Sample 6—Angel Whispers in a non-vented jar.
- g) Test Sample 7—Angel whispers in a non-vented jar with a wick clip, i.e., a metallic clip with wing-shaped extensions on two sides of the wick clip.

The results for Test Sample 1 and Test Sample 2—Tender Flowers—are similar to the results for Test Sample 3 and Test Sample 4—Apple & Cinnamon (detailed below). The candles burned while having a screen on top of the jar produced less emissions compared to the candles burned without a screen. (The screen on top of the jar simulates a candle topper or chimney such as disclosed in U.S. Pat. Nos. 6,589,047 and 6,585,510). The results for Test Sample 1 and Test Sample 2 are shown, for example, in FIG. 16.

The results for Test Sample 3 and Test Sample 4—Apple & Cinnamon—The five candles with a screen on top showed less emissions compared to the five candles burned without the screen. The screen on top of the jars modified air flow during candle burning which prevented the flame from flickering. Less flame flickering minimized the amount of particulate emitted by the candle. The results for Test Sample 3 and Test Sample 4 are shown, for example, in FIG. 17.

Test Sample 6—Angel Whispers candles burned in non-vented jars and Test Sample 5—Angel Whispers candles burned in vented jars having hole patterns in accordance with the invention showed the most significant difference in the amount of emissions collected on the filters. Cumulative amount of particulate emissions from Test Sample 5 in vented jars was significantly less than the amount of particulate emissions collected from the first four hour burn of Test Sample 6—Angel Whispers in non-vented jars.

Filters from Test Sample 6—Angel Whispers candles burned in non-vented jars and Test Sample 5—Angel Whispers candles burned in vented jars are shown, for example, in FIG. 18. The Angel Whispers candles in vented jars burned with significantly less particulate emissions.

Test Sample 6—Angel Whispers candles burned in non-vented jars have the highest amount of particulates and were the only one that produced a powdery carbon deposit on the filter. Test Sample 7—Angel Whispers candles in non-vented jars with wick clips were slightly cleaner burning, but not as clean as Test Sample 5—Angel Whispers candles burned in vented jars, as shown, for example, in FIG. 19.

The optical density measurements for the Test Samples 1-7 are shown in TABLE 1 below. Each data point is an average of the optical density measurements of the five filters in each Test Sample. The optical density measurements for the Test Samples are shown in FIG. 20.

TABLE 1

T.S. 1 - Tender
T.S. 2 - Tender
T.S. 3 - Apple
T.S. 4 - Apple
T.S. 5 - Angel
T.S. 6 - Angel
T.S. 7 - Angle

Time
Flowers With
Flowers Without
& Cinnamon With
& Cinnamon
Whispers In
Whispers In
Whispers With

Measured
Screen
Screen
Screen
Without Screen
Vented Jars
Non-Vented Jars
Wick Clip

0-4
0.08
0.03
0.13
0.24
0.004
0.05
0.07

hours

4-8
0.07
0.07
0.09
0.17
0.02
0.14
0.06

hours

8-12
0.1
0.04
0.17
0.27
0.05
0.14
0.11

hours

12-16
0.13
0.08
0.25
0.35
0.07
0.26
0.15

hours

16-20
0.15
0.11
0.3
0.4
0.09
0.36
0.34

hours

20-24
0.18
0.026
0.33
0.47
0.1
0.73
0.53

hours

24-28
0.2
0.08
0.35
0.52
0.1
1.19
0.60

hours

28-32
0.22
0.18
0.37
0.57

0.64

hours

32-36
0.23
0.46
0.39
0.6

hours

36-40
0.29
0.8
0.41

hours

40-44
0.29

hours

44-50
0.31

hours

T.S. = Test Sample

Side Wall and Bottom Temperature: Using the thermocouple board, side wall and bottom temperatures of the vented jars and the non-vented jars were measured. The temperature was measured at five different locations while candles were burning from the beginning to the end of life. The maximum side wall temperature of the vented jars was lower and dissipates readily compared to the non-vented jars. The side wall and bottom temperatures of vented jars are more consistent compared to non-vented jars. These results are shown for example in FIGS. 21 and 22.

Weight Loss: With limited number of samples burned to compare vented jars and non-vented jars weight loss (five of each), the observed burn rate of each candle mirrored each other. The burn rate of candles in vented jars was very consistent from beginning to end of candle life. The burn rate standard deviation of Test Sample 6—Angel Whispers in non-vented jars was significantly larger than Test Sample 5—Angel Whispers in vented jars.

Candles burned without a screen are shown for example in FIG. 23. Candles burned with a screen on top are shown for example in FIG. 24.

After the tests, the following conclusions were reached:

(1) Candles in vented jars having hole patterns in accordance with the invention, i.e., having laminar air flow therethrough, are the cleanest burning, none of the candles produced soot or any dark emission.

(2) Candles burned with the screen on top performed better than the candles burned without the screen. The non-vented jars in this test produced the most soot.

(3) Candles with a wing-shaped wick clip burned in non-vented jars produced less emission and lower retention than candles with a regular wick clip, i.e., no side extensions, burned in non-vented jars. The wing-shaped extensions of the wick clip minimized the flickering of the flame towards candle end of life.

(4) Similarity between vented jars and jars with a screen is the change in air flow pattern. Vents and screens on the jar produced a more laminar air flow which prevents the flame from flickering. Flickering of the flame generally produces more emission.

(5) Side wall and bottom wall temperatures of vented jars were lower than that in non-vented jars.

(6) Performances of candles in vented jars are very consistent. The burn rate, side wall temperature and bottom wall temperature profile are very similar in all samples.

(7) The weight of a vented jar is about 120 grams less than the weight of a non-vented jar. This weight difference is an advantage, including providing a shipping cost savings.

Also, a candle emission study preliminary screen evaluation was conducted. For the candle emission test, screens were made. The screens were made out of aluminum mesh screen and were cut into 5 inch by 5 inch (5″×5″) square with a 1 inch (1″) diameter hole in the middle. To evaluate the effects of the screen on the candle during burning, three candles with screens and three candles without screens were burned using candle burn test protocol. All candles were observed for emission of VOCs and particulates. AQS performed the candle emission study similar to TNO, only using a larger room, e.g., 26 m³instead of 2.2 m³.

After the study was completed, the following observations were made:

(1) The flame of candles without a screen, from beginning to end of life, showed more flickering (causes sooting).

(2) One out of the three candles without a screen formed bigger bloom.

(3) One out of three candles showed pronounced carbon deposit on a top portion of the jar.

(4) The flame of the candles with a screen was very consistent in size and was without flickering.

(5) None of the three candles with a screen showed carbon deposit or coking.

(6) The burn rate for the candles with a screen was more consistent, having an average retention of about 2 grams less than the candles without a screen.

(7) Candles with a screen have slightly longer burn life compared to candles without a screen.

Candles burned without a screen are shown, for example, in FIG. 23. Candles burned with a screen on top are shown, for example, in FIG. 24.

Next, the following test steps were conducted:

(1) Screens were sent to AQS for candle emission study.

(2) The same formula of “Tender Flowers” and “Apple & Cinnamon” tested by TNO were sent to AQS for emission study.

(3) Samples were tested for VOCs and particulates.

(4) Whether there is a significant difference in the amount of emission/particulates was determined between candles with and without a screen.

During testing, aluminum screens were tested for formaldehyde using a Draeger tube to ensure no additional VOC emission comes from the screen. All screens were cured at 105° C. (221° F.) for 30 hours to volatilize any coating used during screen manufacturing.

AQS measured VOCs and particulates. The optical method for comparison of candle emissions of the invention are detailed below.

The total emissions from a candle are collected on a filter over a defined period of time. The emissions can be quantified by measuring the light reflectance from the filter using an optical densitometer in the reflection mode. By dividing the measured Optical Density (OD) by the individual candle burn rate, a relative comparison can be made between candles for emissions, even when the candles burn at different rates. This makes the soot measurement indicative of the efficiency of combustion rather than a measure that reflects the amount of fuel delivered to the flame.

The apparatus and materials used to determine the candle emissions were as follows:

(1) 60 HZ, 1725 RPM, ¾ hp vacuum pump.

(2) Heat resistant Teflon tubing ¼ inch (12.7 cm) used to connect pump with plumbing apparatus and to connect collection devices to flowmeters.

(3) Plumbing apparatus with connection to vacuum pump and six separate, parallel outlets for connection to flowmeters (3 on each side of rectangular shaped apparatus).

(4) Six Dwyer RMB series 0-100 SCFH flowmeters connected to the above plumbing apparatus.

(5) Six collection devices consisting of two 5 inch (12.7 cm) threaded steel tubes connected to each other in the middle by a Y-connector, a 3 inch (7.6 cm) threaded steel tube extending perpendicular to the 5 inch (12.7 cm) steel tubes, and an aluminum collection cone designed with grooves for increased surface area and increased heat loss.

(6) Six 47 mm support screens which fit into the base of the collection cone.

(7) Gelman Type A/E 47 mm glass fiber filters.

(8) Six cylindrical glass tubes 2⅛ inch (5.4 cm) ID by 6 inch (15.2 cm).

(9) Six draft deflection units consisting of two perforated steel cylinders of different diameter with the smaller one placed inside the larger one (large is 23.3 cm×35.9 cm, small is 20.6 cm×35.9 cm). The cylinders should be arranged so that there is minimal overlap of the individual perforations. A draft deflection made of two layers of window screening is also acceptable.

(10) Lab stands or blocks to bring the candle up to the center of the steel cylinder.

(11) Standard laboratory stands and clamps to hold the glass tubes in place.

(12) Mettler PM4600 scale used for candle weight measurements.

(13) Stainless steel flat and pointed tweezers for filter handling.

(14) Ruler for measuring distance between glass tube and candle.

(15) Fisherbrand tight lid 47 mm petri dishes for used filter storage.

(16) Six digital timers.

The candle emissions tests were conducted in accordance with the following procedure:

(1) Each glass filter was placed on a 47 mm support screen at the base of an aluminum collection cone and the airflow adjusted to 21 SCFH (cubic feet per hour at standard conditions). This was considered the maximum flow rate attainable from the pump when all six units were operating simultaneously. Airflow was established prior to placing the filters on the devices in order to keep the filters in place. The collection devices were not placed atop the glass tubes at this stage.

(2) The five candles were labeled and the wicks trimmed to one-quarter inch (0.64 cm).

(3) The weight of each candle was taken with the Mettler PM4600 scale and recorded.

(4) Each candle was lit and allowed to burn for 5 minutes (which established a melt pool, or the liquid portion of the wax that collects near the flame).

(5) The weight of each candle was taken again and recorded.

(6) Each lit candle was positioned so that the top of the container or side wall was at approximately one-half the height of the draft deflector using a lab stand or blocks.

(7) The glass tubes were adjusted so the candle flame was centered beneath each tube.

(8) The height of each glass tube was adjusted so there was 3 cm between the bottom of the glass tube and the rim of the glass of the candle. When testing candles that were not in jars, the glass tube was adjusted so that it was 3 cm from the top of the candle. This allowed for adequate ventilation of the candles and helped minimize heat build-up.

(9) Each collection device, with glass filter in place, was placed atop its respective glass tube. The aluminum collection cone was fit snugly into the glass tube to eliminate loss of emissions.

(10) The candles were allowed to burn for 2 hours.

(11) After 2 hours, each collection device was removed from its glass tube and all the candles blown out.

(12) The weight of each glass filter was then taken and recorded.

(13) Each filter was placed in a labeled tight lid petri dish.

(14) The weight of each candle was then taken and recorded.

After testing, the following information/results was determined:

(1) The total mass of candle consumed (weight of candle after 5 minute pre-burn minus weight of candle at end of testing).

(2) The burn rate in grams per hour (mass lost from each candle divided by hours burned).

(3) The amount of candle emissions collected divided by the burn rate.

The gravimetric specifications are shown in FIGS. 25-27. As indicated above, a candle's weight lost per hour is used to calculate optical density per burn rate. This shows how much soot or particulates is generated within a specific burn period. FIGS. 25-27 are schematic diagrams of a cross-sectional view of an aluminum collection cone. FIG. 25 shows the opening at the top of the collection cone. This opening serves as the outlet for ambient air and candle emission that passed through the fiberglass filter. FIG. 26 shows a schematic view of the bottom section of the collection cone where the support screen and fiberglass filter are placed during the soot emission test. FIG. 27 is a diagram of the aluminum collection cone showing eight cooling slots at 0.3 cm intervals and the conical shape inside the cylindrical shape collection cone. The top and bottom edges are preferably wider.

The testing and data collected show the significance of controlling the air flow in a containerized candle to reduce or effectively eliminate carbon particulate emission. A non-sooting candle is, thus, provided which is desirable both environmentally and aesthetically.

The exemplary embodiments herein disclosed are not intended to be exhaustive or to unnecessarily limit the scope of the invention. The exemplary embodiments were chosen and described in order to explain the principles of the present invention so that others skilled in the art may practice the invention. As will be apparent to one skilled in the art, various modifications can be made within the scope of the aforesaid description. Such modifications being within the ability of one skilled in the art form a part of the present invention and are embraced by the appended claims.

Non-sooting containerized candle

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