U.S. patent application number 10/295056 was filed with the patent office on 2003-07-03 for self extinguishing candles and method of making same.
Invention is credited to Elliott, David III, Morrison, David, Thompson, Julie.
Application Number | 20030124474 10/295056 |
Document ID | / |
Family ID | 32312165 |
Filed Date | 2003-07-03 |
United States Patent
Application |
20030124474 |
Kind Code |
A1 |
Elliott, David III ; et
al. |
July 3, 2003 |
Self extinguishing candles and method of making same
Abstract
A self-extinguishing candle and method of making the candle are
described. The self-extinguishing candle comprises a candle body
formed of a candle base material and a flame retardant. The flame
retardant is capable of extinguishing the candle flame or,
alternatively, of controlling the candle flame.
Inventors: |
Elliott, David III;
(Pearland, TX) ; Morrison, David; (The Woodlands,
TX) ; Thompson, Julie; (The Woodlands, TX) |
Correspondence
Address: |
JENKENS & GILCHRIST, A PROFESSIONAL CORPORATION
1100 LOUISIANA
SUITE 1800
HOUSTON
TX
77002-5214
US
|
Family ID: |
32312165 |
Appl. No.: |
10/295056 |
Filed: |
November 13, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10295056 |
Nov 13, 2002 |
|
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09874669 |
Jun 5, 2001 |
|
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60210057 |
Jun 7, 2000 |
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Current U.S.
Class: |
431/35 |
Current CPC
Class: |
C11C 5/008 20130101;
C11C 5/002 20130101 |
Class at
Publication: |
431/35 |
International
Class: |
F23N 005/00 |
Claims
What is claimed is:
1. A candle comprising: a candle body comprising: a candle base
material; a flame retardant; and a wick, wherein the flame
retardant is substantially uniformly distributed throughout the
candle body.
2. The candle of claim 1 wherein the flame retardant is selected
from the group consisting of hydrophobic silica, liquid silicone,
titanium dioxide, clay, diatomaceous earth, and mixtures
thereof.
3. The candle of claim 1 wherein the flame retardant is selected
from the group consisting of aluminum oxide, alumina trihydrate,
magnesium hydroxide, magnesium carbonate, calcium carbonate, boric
acid, antimony trioxide, and mixtures thereof.
4. The candle of claim 1 wherein the flame retardant is selected
from the group consisting of tris-(1,3-dibromopropyl) phosphate,
ammonium phosphate, bis(bromochloropropyl) bromochloropropyl
phosphate, chlorinated paraffin, polybrominated diphenyloxide,
decarbromophenoxybenzene, tetrabromobisphenol A,
hexabromocyclododecane, tetrabromophthalic anhydride, and mixtures
thereof.
5. The candle of claim 1 wherein the candle body contains from
about 0.01% to 50% by weight flame retardant.
6. The candle of claim 1 wherein the candle body contains from
about 0.05% to about 20% by weight flame retardant.
7. The candle of claim 1 wherein the candle body contains from
about 0.1% to about 10% by weight flame retardant
8. The candle of claim 1 wherein the candle base material includes
a wax.
9. The candle of claim 8 wherein the wax is selected from the group
consisting of paraffin wax, microcrystalline wax, beeswax, animal
wax, insect wax, vegetable wax, mineral wax, synthetic wax,
polyethylene wax, and mixtures thereof.
10. The candle of claim 1 wherein the candle base material includes
a wax and a gelling agent.
11. The candle of claim 8 wherein the gelling agent is a di-block
copolymer, tri-block copolymer, radial copolymer, star polymer,
multi-block copolymer, a polyamide, an ester terminated polyamide,
an amide terminated polyamide, polyamide derivatives,
polybutadiene, or a mixture thereof.
12. The candle of claim 1 wherein the candle base material includes
a hydrocarbon oil.
13. The candle of claim 1 wherein the candle body further comprises
one or more soluble, partially soluble or insoluble embeds, or a
mixture thereof.
14. The candle of claim 1 wherein the flame retardant is present in
at least a flame-extinguishing concentration.
15. The candle of claim 1 wherein the flame retardant is present in
a flame-controlling amount.
16. The candle of claim 2 wherein the flame retardant restricts the
flow of candle base material through the wick.
17. A candle comprising: a candle body having a lightable end and
bottom end and comprising: a candle base material; a flame
retardant; and a wick, wherein the flame retardant is distributed
in the candle body in a gradient with a flame-extinguishing
concentration of flame retardant at the bottom end and a lower
concentration of flame retardant at the lightable end.
18. The candle of claim 17 wherein the flame retardant is selected
from the group consisting of hydrophobic silica, liquid silicone,
titanium dioxide, clay, diatomaceous earth, and mixtures
thereof.
19. The candle of claim 17 wherein the flame retardant is selected
from the group consisting of aluminum oxide, alumina trihydrate,
magnesium hydroxide, magnesium carbonate, calcium carbonate, boric
acid, antimony trioxide, and mixtures thereof.
20. The candle of claim 17 wherein the flame retardant is selected
from the group consisting of tris-(1,3-dibromopropyl) phosphate,
ammonium phosphate, bis(bromochloropropyl) bromochloropropyl
phosphate, chlorinated paraffin, polybrominated diphenyloxide,
decarbromophenoxybenzene, tetrabromobisphenol A,
hexabromocyclododecane, tetrabromophthalic anhydride, and mixtures
thereof.
21. The candle of claim 17 wherein the candle base material
includes a wax.
22. The candle of claim 21 wherein the wax is selected from the
group consisting of paraffin wax, microcrystalline wax, beeswax,
animal wax, insect wax, vegetable wax, mineral wax, synthetic wax,
polyethylene wax, and mixtures thereof.
23. The candle of claim 17 wherein the candle base material
includes a wax and a gelling agent.
24. The candle of claim 23 wherein the gelling agent is a di-block
copolymer, tri-block copolymer, radial copolymer, star polymer,
multi-block copolymer, a polyamide, an ester terminated polyamide,
an amide terminated polyamide, polyamide derivatives,
polybutadiene, or a mixture thereof.
25. The candle of claim 17 wherein the candle base material
includes a hydrocarbon oil.
26. The candle of claim 17 wherein the candle body further
comprises one or more soluble, partially soluble or insoluble
embeds, or a mixture thereof.
27. A candle comprising: a candle body having a top lightable
portion and a bottom portion wherein the top portion comprises a
candle base material and the bottom portion comprises a candle base
material and a flame retardant, and a wick extending from the top
lightable portion through at least part of the candle body.
28. The candle of claim 27 wherein the flame retardant is selected
from the group consisting of hydrophobic silica, liquid silicone,
titanium dioxide, clay, diatomaceous earth, and mixtures
thereof.
29. The candle of claim 27 wherein the flame retardant is selected
from the group consisting of aluminum oxide, alumina trihydrate,
magnesium hydroxide, magnesium carbonate, calcium carbonate, boric
acid, antimony trioxide, and mixtures thereof.
30. The candle of claim 27 wherein the flame retardant is selected
from the group consisting of tris-(1,3-dibromopropyl) phosphate,
ammonium phosphate, bis(bromochloropropyl) bromochloropropyl
phosphate, chlorinated paraffin, polybrominated diphenyloxide,
decarbromophenoxybenzene, tetrabromobisphenol A,
hexabromocyclododecane, tetrabromophthalic anhydride, and mixtures
thereof.
31. The candle of claim 27 wherein the bottom portion of the candle
body contains from about 0.01% to 50% by weight flame
retardant.
32. The candle of claim 27 wherein the bottom portion of the candle
body contains from about 0.05% to about 20% by weight flame
retardant.
33. The candle of claim 27 wherein the bottom portion of the candle
body contains from about 0.1% to about 10% by weight flame
retardant
34. The candle of claim 27 wherein the candle base material
includes a wax.
35. The candle of claim 34 wherein the wax is selected from the
group consisting of paraffin wax, microcrystalline wax, beeswax,
animal wax, insect wax, vegetable wax, mineral wax, synthetic wax,
polyethylene wax, and mixtures thereof.
36. The candle of claim 27 wherein the candle base material
includes a wax and a gelling agent.
37. The candle of claim 36 wherein the gelling agent is a di-block
copolymer, tri-block copolymer, radial copolymer, star polymer,
multi-block copolymer, a polyamide, an ester terminated polyamide,
an amide terminated polyamide, polyamide derivatives,
polybutadiene, or a mixture thereof.
38. The candle of claim 27 wherein the candle base material
includes a hydrocarbon oil.
39. The candle of claim 27 wherein the candle body further
comprises one or more soluble, partially soluble or insoluble
embeds, or a mixture thereof.
40. The candle of claim 28 wherein the flame retardant restricts
the flow of candle base material through the wick.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. patent
application Ser. No. 09/874,669 filed on Jun. 5, 2001 which claims
priority to U.S. Provisional patent application, Serial No.
60/210,057, filed Jun. 7, 2000, the disclosures of which are
incorporated by reference herein in their entirety.
FEDERALLY SPONSORED RESEARCH
[0002] Not applicable.
REFERENCE TO MICROFICHE APPENDIX
[0003] Not applicable.
FIELD OF THE INVENTION
[0004] The invention relates to self-extinguishing candles and
methods of making candles.
BACKGROUND OF THE INVENTION
[0005] Since their earliest use, candles have provided a convenient
and generally reliable source of light for mankind. While candles
have varied substantially through the years, all generally comprise
a solid fuel source (usually wax) within which a fiber wick is
embedded. In their basic function, candles provide light once the
fiber wick is lit by producing sufficient heat to melt the wax fuel
to a liquid form which may be carried within the wick and burned.
As the candle flame burns, the heat produced creates a pool of
melted wax in the region of the wick. This liquified or melted wax
is then carried up to the flame by capillary action within the
wick. As the candle burns, and the wax fuel is consumed, the
position of the flame moves downwardly upon the wick permitting the
candle to produce a substantially continuous light.
[0006] As long as the fuel is supplied through the wick via a
capillary action to the flame, the flame continually bums down the
wick. In many situations, the candle is lit and left alone to bum
until the candle is manually extinguished or extinguishes itself. A
typical candle will normally extinguish itself upon the
disintegration of the wick or the elimination of the fuel supply to
the wick.
[0007] Many commercially sold wax candles, however, are often
placed or formed in a glass or other fragile non-flammable
container. Therefore, as the flame disintegrates the wick, the
flame approaches the bottom of the glass candle holder, thereby
causing the glass holder to experience excessive heating. In
certain conditions, the excessive heating results in thermally
induced cracking or breakage failures. Specifically, when the heat
inside the glass container exceeds the heat stress limits of the
glass container, the glass may crack or completely break. If a
glass candle holder breaks, flying glass pieces, fire hazards, and
bums from picking up hot pieces of glass and wax may result in
various levels of injury and/or property damage.
[0008] Typical candles will often self-extinguish when
approximately 0.25 inches of wax residue is left in the bottom of
the glass holder. However, allowing a candle to bum with only 0.25
inches of wax residue between the flame and bottom of the glass is
often dangerous in that, as discussed above, the flame still
provides excessive heat to the glass surface. To further separate
the flame from the glass surface and to provide stability to the
wick, the bottom end of the wick is typically inserted into a wick
clip. An exemplary wick clip is often constructed of a thin metal
or aluminum material which includes a wide base for supporting a
hollow cylindrical ferrule, whereby the cylindrical ferrule is
typically located in the center of the base. The center of the base
often includes an opening allowing fuel access from underneath the
base into the hollow ferrule.
[0009] Other candles, such as pillar candles, are free-standing,
neither poured nor placed into a holder. As the candle bums down,
the flame approaches the surface on which the candle is placed and
may mar, char or bum the surface. If a free-standing candle is left
unattended and is allowed to bum very low, the melted wax could
flow out of candle and over the surface. Furthermore, as the flame
approaches the bottom of the wick, a free-standing candle poses a
safety hazard as the flame could ignite the surface on which the
candle sits.
[0010] Alternatively, some candles, both free-standing and jar
candles, are manufactured to include a wick holder formed from a
round base with a cylindrical ferrule emanating from the center of
the round base. The cylindrical ferrule is hollow as to allow one
end of the wick to be reciprocally received therein. The upper
portion of the ferrule is "S" crimped, without piercing the
ferrule, to reduce the flow of fuel upward through the ferrule. The
base of the wick holder includes a small opening in the center of
the base which is concentric with, and the same diameter as, the
opening in the cylindrical ferrule. The bottom of the base, on the
opposite side of the cylindrical ferrule, is completely sealed off
by a hot-melt adhesive, thereby preventing fuel from traveling up
the hollow ferrule.
[0011] By reducing the flow of fuel within the wick holder, the
wick holder restricts the supply of fuel to the candle wick when
the flame burns the candle wick down to the top of the wick holder
ferrule. By restricting the supply of fuel to the wick, the candle
flame, upon burning down to the top of the wick holder,
self-extinguishes before allowing the flame to approach the surface
of the glass candle holder.
[0012] The aforementioned candles are based on restricting the flow
of liquid wax to the wick by a mechanical device. Therefore, the
ability of the candles to self-extinguish depends upon the
performance of the restricting device. If the restricting device
fails to function, the candle would not self-extinguish at the
desired point. Therefore, there is need for a candle that
self-extinguishes at the desired point with improved
consistency.
[0013] It has also been observed that candles frequently burn with
too large a flame and expend the candle too quickly. Although the
wick can be manually trimmed to decrease the flame size, this
necessitates extinguishing the candle and allowing the wick to
cool. Furthermore, trimming the wick does not prevent the rapid
consumption of the candle. There is a need, therefore, for a candle
in which the rate of fuel consumption, and therefore flame size, is
controlled.
SUMMARY OF THE INVENTION
[0014] Embodiments of the invention meet the aforementioned need by
one or more of the following aspects. In one aspect, a
self-extinguishing candle is provided. The self-extinguishing
candle includes a candle body formed of a candle base material, and
a wick. All or part of the candle body includes at least one flame
retardant as an additive.
[0015] The flame retardant in accordance with the embodiments of
the invention may be a solid insoluble or partially soluble in the
candle base material. In some embodiments, the flame retardant may
function by flowing into and partially or totally clogging the wick
thereby restricting or preventing the flow of the candle base
material into and through the wick. As a consequence, the flame may
be limited and/or controlled or extinguished.
[0016] Alternatively, the flame retardant in accordance with the
embodiments of the invention may be a flame-extinguishing or
flame-controlling, non-combustible, material which flows into and
through the wick. In such embodiments, the flame retardant either
limits and/or extinguishes the flame. Such material may be a solid
or a liquid. The clogging-form, flame-controlling, and the
flame-extinguishing form of flame retardants are collectively
referred to herein as a flame retardant.
[0017] In one embodiment, the self-extinguishing candle includes a
candle body formed from a candle base material and having a bottom
portion which further includes at least one flame retardant.
[0018] In another aspect, the self-extinguishing candle includes a
candle body formed from a candle base material and at least one
flame retardant wherein the flame retardant concentration increases
from a low concentration at the top of the candle body, where the
candle is lit, to a high concentration at the bottom of the candle
body.
[0019] In another aspect, a method of making a self-extinguishing
candle is provided. The method includes: (a) forming a candle body
from a candle base material and at least one flame retardant
wherein the flame retardant is evenly distributed throughout the
candle body.
[0020] Additional aspects of the invention as well as objects and
advantages provided by embodiments of the invention are apparent
with the following description.
DESCRIPTION OF THE DRAWINGS
[0021] Not applicable.
DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0022] Embodiments of the invention provide a self-extinguishing
candle which includes a candle body formed of a candle base
material. In a first embodiment, the candle body further includes a
substantially uniformly distributed flame retardant additive. The
flame retardant may be present in amounts from about 0.01% to about
50% by weight; more preferably, from about 0.05% to about 20% by
weight; and most preferably, from about 0. 1% to about 10% by
weight.
[0023] The terms "flame retardant additive" and "flame retardant"
as used herein mean any compound, composition or material which
extinguishes and/or controls a flame. These terms include
solid-clogging, flame extinguishing and flame limiting forms.
[0024] In a second embodiment, the distribution of flame retardant
is non-uniform, with a greater concentration of the flame retardant
in a lower portion of the candle body. Most preferably, there
exists a gradient of increasing flame retardant weight percentage
over the height of the candle, having from about 0% to about 10%
flame retardant at the top of a candle nearest the lightable end of
the candle to from about 90% to about 0.01% flame retardant at the
bottom of the candle.
[0025] In yet another embodiment, the flame retardant concentration
is discontinuous, with no flame retardant present toward a
lightable end of the candle body and a flame-extinguishing
concentration of a flame retardant present toward the bottom of the
candle body. The flame retardant may range from about 0.01% to
about 90% by weight toward the bottom portion of the candle
body.
[0026] In some embodiments, the flame retardant is of the type or
in sufficient concentration to completely extinguish the flame. In
other embodiments, the flame retardant is of the type or in a
concentration so as to control the flame such that the flame does
not burn excessively or stronger than desired. Particularly useful
for controlling the flame are the solid, insoluble clogging forms
of flame retardants. Such clogging flame retardants, including but
not limited to hydrophobic silica, restrict the flow of the candle
base material to and/or through the wick.
[0027] Typically, the self-extinguishing candle includes one or
more wicks inside or on the outside of the candle, although it is
not always necessary to have a wick inside the candle. The wick may
extend completely or partially through the candle body. Wickless
candles which are self-extinguishing may also be made in accordance
with embodiments of the invention.
[0028] The candle body of the self-extinguishing candle in
accordance with embodiments of the invention includes a candle base
material. The term "candle base material" refers to any material
that can be used to form a candle. A suitable candle base material
preferably is a solid which upon melting, provides a fuel source to
a burning wick. A suitable candle base material can be solid,
semi-solid, or liquid. Although most candle base material is opaque
or substantially opaque, a transparent, substantially transparent
or translucent material can also be used to form the candle body.
Consequently, the self-extinguishing candles in accordance with
embodiments of the invention can be transparent, opaque, or
translucent.
[0029] A common form of candle base material is wax, which usually
refers to a substance that is a plastic to brittle solid at ambient
temperature and becomes a low viscosity liquid upon being subjected
to elevated temperatures. Suitable waxes for forming the candle
body include any known waxes, including but not limited to,
paraffin wax, microcrystalline wax, beeswax, insect wax, animal
wax, vegetable wax, mineral wax, synthetic wax, polyethylene wax,
and mixtures thereof. In addition to wax, semi-solids (such as
petrolatum), liquids, synthetic materials, synthetic polymers,
mixtures of synthetic materials, mixtures of synthetic polymers and
synthetic materials, and mixtures of synthetic polymers with one or
more organic compounds may be used as a candle base material or
part of a candle base material. Other typically used candle fuel
source components, such as hydrocarbon oil, stearic acid,
Vybar.RTM., etc., also may be included in the candle base material.
The following U.S. patents disclose a suitable candle base material
that can be used in embodiments of the invention: U.S. Pat. Nos.
6,063,144; 6,036,925; 4,855,098; 4,449,987; 4,332,548; and U.S.
Pat. No. 4,005,978. The disclosures of all of the above U.S.
patents are incorporated by reference herein in their entirety. It
is noted that a wax can be used alone or with one or more additives
or gelling agents to form the candle base material, depending on
the type of candles desired.
[0030] The self-extinguishing candle can also have a translucent,
transparent or substantially transparent candle body. Any
translucent, or transparent candle base material may be used in
embodiments of the invention. For example, the following U.S.
patents disclose a suitable transparent candle composition which
may be used in embodiments of the invention: U.S. Pat. No.
5,879,694; 5,843,194; 5,578,089; 5,508,334; 5,132,355; 3,819,342;
and U.S. Pat. No. 3,645,705. In addition, U.S. Pat. No. 6,111,055
discloses a transparent polyamide-based gel that can be used to
form a transparent candle. As the terms are used herein, polyamides
may be considered either a synthetic material or a synthetic
polymer. The disclosures of all of the above U.S. patents are
incorporated by reference herein in their entirety. In addition,
U.S. Pat. No. 5,961,967 discloses a multiphase candle containing
locally enriched regions of deliverable active ingredients. Such a
candle may also be used in embodiments of the invention. Therefore,
the disclosure of this patent is incorporated by reference herein
in its entirety.
[0031] In some embodiments, the candle body may be formed from a
candle base material which is capable of undergoing a phase
transition from opaque to transparent or vice versa. PCT
Application WO 99/27042 discloses such a candle base material which
is suitable for use in embodiments of the invention. The disclosure
of this PCT application is incorporated by reference herein in its
entirety. Moreover, U.S. Pat. No. 6,471,731, entitled "Polymeric
Candle Compositions and Candles Made Therefrom," filed on Oct. 29,
2002 and U.S. patent application Ser. No. 09/590,863, filed on Jun.
9, 2000 in the name of David Elliott, III, Richard L. Johnson, Wei
Song as the inventors, disclose another candle base material which
is capable of under going a phase transition from opaque to
transparent. The disclosures of these provisional and utility
applications are incorporated by reference herein in its
entirety.
[0032] The flame retardants disclosed in The Chemistry and Uses of
Fire Retardants by J. W. Lyons, Wiley-Interscience (1970), can be
used in this invention. Thus, the disclosure of this book is
incorporated by reference herein in its entirety. It is noted that
a suitable flame retardant can be an inorganic compound, an
organometallic compound, an organic compound, or a mixture thereof.
The flame retardant can be liquid, solid, or semi-solid.
Hydrophobic silica, titanium dioxide (TiO.sub.2), talc,, clay,
diatomaceous earth, and liquid silicone may be used as a flame
retardant. Additional suitable flame retardants include, but are
not limited to, lead-containing compounds, arsenic-containing
compounds, phosphorus-containing compounds, sulfur-containing
compounds, alumina trihydrate, aluminum oxide (Al.sub.2O.sub.3),
magnesium hydroxide, magnesium carbonate, calcium carbonate, boric
acid, antimony trioxide, tris-1,3-dibromopropyl phosphate, ammonium
phosphate, bis(bromochloropropyl) bromochloropropyl phosphate,
chlorinated paraffin, polybrominated diphenyloxide,
decarbromophenoxybenzene, tetrabromobisphenol A,
hexabromocyclododecane, tetrabromophthalic anhydride, or mixtures
thereof. Additional suitable flame retardants are disclosed in the
following U.S. Pat. Nos. 6,005,033; 5,886,072; 5,766,568;
5,710,202; 5,583,172; 5,578,666; 5,532,302; 5,521,003; 5,418,272;
5,344,855; 5,296,534; 5,027,416; 5,185,103; 5,151,225; 5,130,349;
5,030,674; 5,025,042; 5,011,736; 4,945,018; 4,921,897; 4,900,768;
4,885,318; 4,869,948; 4,808,647; 4,740,537; 4,671,896; 4,520,152;
4,456,654; 4,362,658; 4,350,793; 4,343,854; 4,320,038; 4,235,978;
4,194,068; 4,184,969; 4,154,775; 4,115,351; 4,094,850; 4,078,016;
4,067,930; 3,956,567; 3,953,650; 3,950,456; and U.S. Pat. No.
3,941,908. The disclosures of all of the above U.S. patents are
incorporated by reference herein in their entirety. Moreover,
suitable flame retardants include a phosphorus/nitrogen-containing
oligomer or polymer as disclosed in U.S. Pat. No. 5,409,976, a
phosphorus/nitrogen-containing compound as disclosed in U.S. Pat.
No. 5,158,999, a halogenated aliphatic bisimide as disclosed in
U.S. Pat. No. 4,430,467, and thermally stable cyclic phosphonate
esters as disclosed in U.S. Pat. No. 4,842,609, and halogenated
imide-containing polyols as disclosed in U.S. Pat. No. 4,401,778.
The disclosures of all of the preceding U.S. patents are
incorporated by reference herein in their entirety.
[0033] In some embodiments of phase-changing candles, paraffin wax
with at least 20 carbon atoms per molecule (hereinafter "C.sub.20+
paraffin wax") is used. C.sub.20+ paraffin wax refers to a wax
composed of mainly paraffins with 20 or more carbon atoms per
molecule. In other words, the preferred C.sub.20+ paraffin wax is
substantially free of paraffins with less than 20 carbon atoms per
molecule. Nevertheless, a small amount of paraffins with less than
20 carbon atoms per molecule may be present in the C.sub.20+
paraffin wax. Preferably, the melting point of the C.sub.20+
paraffin wax should fall in the range of about 100.degree. F. to
about 200.degree. F. (i.e., about 37.degree. C. to about 93.degree.
C.), more preferably in the range of about 100.degree. F. to about
170.degree. F., and most preferably in the range of about
110.degree. F. to about 165.degree. F.
[0034] Paraffin wax is considered as a petroleum wax. It typically
is macrocrystalline and brittle. Paraffin wax usually is composed
of about 40 to about 90 weight percent of normal alkanes, with the
remainder isoalkanes and cycloalkanes. Preferably, the paraffin wax
does not include a substantial amount of hydrocarbons with less
than 20 carbon atoms per molecule. Typical properties of paraffin
wax are listed in Table I as follows. Examples of suitable paraffin
waxes can be obtained from Bareco under the trade names of Bareco
Paraffin 120/125, Bareco FR 5914, and Bareco FR 5315.
1TABLE I Typical Properties of Paraffin Wax FLASH POINT, CLOSED
CUP. .degree. C. 204* VISCOSITY AT 98.9.degree. C., MM.sup.2/S
4.2-7.4 MELTING RANGE, .degree. C. 46-68 REFRACTIVE INDEX AT
98.9.degree. C. 1.430-1.433 NUMBER AVERAGE MOLECULAR WEIGHT 350-420
CARBON ATOMS PER MOLECULE 20-36 DUCTILITY/CRYSTALLINITY OF SOLID
WAX friable to crystalline *value is a minimum.
[0035] In some embodiments, wax alone or a mixture of waxes is used
to form the candle body. In other embodiments, a polymer or a
polymeric material is used alone or with a wax to form the candle
base material. In still other embodiments, a wax is mixed with one
or more additives to the form the candle base material. The term
"polymer" used herein includes both homopolymer and copolymer. A
homopolymer is a polymer obtained by polymerizing one type of
monomer, whereas a copolymer is a polymer obtained by polymerizing
two or more types of monomers. "Block copolymer" refers to a
copolymer in which like monomer units occur in relatively long,
alternate sequences on a chain.
[0036] Some polymers used in the candle base material often
function as gelling agents. Any polymer which is capable of forming
a three dimensional network or a gel through physical or chemical
crosslinking may be used in embodiments of the invention. Suitable
polymers include, but are not limited to, a copolymer with at least
two blocks, i.e., a diblock copolymer, a triblock copolymer, a
radial block copolymer, a star polymer, a multi-block copolymer,
and mixtures thereof. Other embodiments, the polymer includes at
least one triblock copolymer, radial block copolymer, star polymer,
or multi-block copolymer. The copolymer includes at least one rigid
block and one elastomeric (or rubber-like) block. The rigid blocks
of the copolymer form rigid domains through which physical
crosslinking may occur. The physical crosslinking via these rigid
domains yields a continuous three dimensional network. In the
presence of heat and shear or solvent, the rigid domains soften and
permit flow. After cooling or solvent evaporation, the rigid
domains reform and harden, locking the elastomeric network in
place. U.S. Pat. No. 5,221,534, U.S. Pat. No. 5,879,694 and U.S.
Pat. No. 5,578,089 disclose examples of such block copolymers, and
the disclosures of the patents are incorporated by reference in
their entirety herein.
[0037] A diblock copolymer includes two blocks within its chains: a
rigid block and an elastomeric block. The rigid block typically may
be composed of polystyrene, polyethylene, polyvinylchloride,
phenolics, and the like; the elastomeric block may be composed of
ethylene/butadiene copolymers, polyisoprene, polybutadiene,
ethylene/propylene copolymers, ethylene-propylene/diene copolymers,
and the like. As such, suitable diblock copolymers include, but are
not limited to, styrene-ethylene/propylene copolymers,
styrene-ethylene/butadiene copolymers, styrene-isoprene copolymers,
styrene-butadiene copolymers. In some embodiments, a diblock
copolymer is used along with one or more triblock copolymers, star
polymers, radial copolymers, and multi-block copolymers.
[0038] A triblock copolymer includes two rigid blocks at either end
and a middle block which is elastomeric within its chains. This is
a preferred triblock copolymer structure, although a triblock
copolymer with two elastomeric end blocks and a rigid middle block
also can be used. Suitable triblock copolymers include, but are not
limited to, styrene-ethylene/propylene-styrene copolymers,
styrene-ethylene/butadiene- -styrene copolymers,
styrene-isoprene-styrene copolymers, and styrene-butadiene-styrene
copolymers. Multi-block copolymers are similar to diblock
copolymers or triblock copolymers, except that the multiple block
copolymers include additional elastomeric blocks and/or rigid
blocks.
[0039] In addition to the linear chain structure, branched
homopolymers or copolymers, such as a radial polymer and a star
polymer, also may be used. It should be noted that one or more
functional groups may be grafted onto the chain of any of the
aforementioned polymers. In other words, any of the above polymers
may be modified by grafting. Suitable functional groups for
grafting depend on the desired properties. For example, one or more
ester groups, silane groups, silicon-containing groups, maleic
anhydride groups, acrylamide groups, and acid groups may be
grafted. In addition to grafting, the above polymers may be
hydrogenated to reduce unsaturation before they are used.
[0040] It is noted that additional suitable block copolymers may
include, but are not limited to, polystyrene/polyester,
polyether/polyamide, polyether/polyester, polyester/polyamide,
polyether/polyurethane, polyester/polyurethane, poly(ethylene
oxide)/poly(propylene oxide), nylon/rubber, and
polysiloxane/polycarbonate.
[0041] Generally, the weight average molecular weight of a suitable
polymer is in the range from about 10,000 to about 1,000,000,
preferably from about 70,000 to about 400,000. The rigid block
content may range from about 5% to about 80%, preferably from about
20% to about 40% by weight.
[0042] Numerous commercially available block copolymers may be used
in embodiments of the invention. For example, various grades of
copolymers sold under the trade name of Kraton.RTM. from Shell
Chemical Company can be used. In addition, copolymers sold under
the trade name of Vector.RTM. available from Dexco and Septon.RTM.
from Kuraray also may be used. Calprene and Solprene products
listed in Table II are available from Momentum Technologies, Inc.
Table II lists some commercially available block copolymers which
may be used in embodiments of the invention.
2TABLE II Block Polystyrene Copolymer Type Content(%) Comment
Kraton .RTM. G 1702 SEP 28 Hydrogenated diblock Kraton .RTM. G 1701
SEP 37 Hydrogenated diblock Kraton .RTM. G 1780 SEP 7 Star polymer
Kraton .RTM. G 1650 SEBS 30 Hydrogenated triblock Kraton .RTM. G
1652 SEBS 30 Hydrogenated triblock Kraton .RTM. D 1101 SBS + SB 31
Triblock and diblock mixture (85:15) Kraton .RTM. D 1102 SBS + SB
28 Triblock + diblock (85:15) Kraton .RTM. D 1133 SBS + SB 35
Triblock + diblock (66:34) Kraton .RTM. FG 1901 SEBS 30 Triblock
(hydrogenated and functionally grafted with 1.7% of maleic
anhydride. Septon .RTM. 1001 SEP 35 Hydrogenated diblock Vector
.RTM. 6030 SB 30 Unsaturated diblock Vector .RTM. 8550 SBS 29
Unsaturated triblock Vector .RTM. 2518P SBS 31 Unsaturated triblock
Calprene .RTM. H6120P SEBS 30 Hydrogenated triblock Solprene .RTM.
1430 SB 40 Unsaturated diblock Note: SEP denotes to
styrene/ethylene/propylene copolymers SEBS denotes to
styrene/ethylene/butylene/styrene copolymers SB denotes to
styrene/butadiene copolymers SBS denotes to
styrene-butadiene-styrene copolymers
[0043] It should be recognized that block copolymers are not the
only polymers that can be used in embodiments of the invention.
Other types of polymers also may be used. Homopolymers which are
capable of effecting strong molecular interaction between polymeric
chains can be used. One such example is butyl rubber, which can
thicken oil due to its compatibility with oil and high molecular
weight. Specifically, a polybutadiene polymer sold under the
trademark of Solprene.RTM. S200, which is available from Momentum
Technologies, Inc., can be used. Other homopolymers capable of
forming hydrogen bonding may include polyamide, polyester, etc.
Other suitable polymers include ester terminated polyamide (ETPA),
amide terminated polyamide (ATPA), other polyamides and polyamide
derivatives.
[0044] In those embodiments in which a polymer is present in a
candle base material, the polymer content may range from about 0.01
wt. % to about 80 wt. %, although other composition ranges are
acceptable. In such embodiments, a polymer is present in the candle
base material from about 1 wt. % to about 65 wt. %. In embodiments
where both a diblock copolymer and a triblock copolymer are used,
the triblock copolymer may range from about 0.01 wt. % to about 30
wt. %, and the diblock copolymer from about 0.01 wt. % to about 20
wt. %.
[0045] In some embodiments of formulating a candle base material, a
wax and a polymer may be present in any amount. In some
embodiments, a candle base material may be made from the following
components: a paraffin wax or a mixture of waxes with at least 20
carbon atoms per molecule in an amount of about 2 to about 96% by
weight, a block copolymer in an amount of about 0.01 to about 35%
by weight, and a hydrocarbon oil in an amount of 0 to about 96% by
weight. Additional additives and objects may be included during the
manufacturing of candles.
[0046] Candle base materials and candle bodies in accordance with
some embodiments of the invention may be prepared by blending a
hydrocarbon oil and a wax with one or more triblock, radial block,
and/or multi-block copolymers, star polymers, or mixtures thereof,
in desired amounts. A diblock copolymer may also be optionally
included. In general, the higher the polymer content, the stiffer
the gel. Acceptable compositions including a hydrocarbon oil, a wax
and polymers are disclosed in U.S. Pat. No. 6,340,467, and the
disclosure of such patent is incorporated by reference in its
entirety herein.
[0047] In some embodiments, a hydrocarbon oil and a suitable wax
are first heated to a temperature in the range of about 50.degree.
C. to about 150.degree. C., at which point a polymer is added under
agitation to the desired weight percent as set forth herein. After
sufficient time for the copolymer to dissolve in the mixture, the
composition is poured into a mold or a jar containing a wick.
Alternatively, a wick may be added thereafter, and the composition
is allowed to cool to a stiff gel.
[0048] In some embodiments of the invention, the candle is formed
by cooling the candle base material with flame retardant additive
in a mold or jar. A mold is used to impart external features, for
example, a pillar candle, if desired. Conventional jars, clear,
colored or otherwise decorative, such as sculpted, etched, cut
glass, etc., may be employed for holding the candle. More
preferably, clear glass jars are used for a jar candle.
[0049] Candle base materials and candle bodies also may be formed
by blending a suitable polymer (or a polymer blend) and a
hydrocarbon oil and heating the mixture to a temperature in the
range of from about 50.degree. C. to about 150.degree. C. to
dissolve the polymer (or the polymer blend) in the oil. A wax is
then added under agitation. The wax is mixed with the hydrocarbon
oil and the copolymer. Mixing may be carried out in any
conventional manner. Upon cooling, a stiff (and sometimes opaque)
gel forms.
[0050] In addition to a wax and a polymeric material, a hydrocarbon
oil may be used in forming a candle base material. It is noted that
a hydrocarbon oil may used with or without a polymeric material in
formulating a candle base material. Hydrocarbon oil refers to any
oil that is primarily composed of one or more compounds with
hydrocarbon moieties. Suitable hydrocarbon oils include, but are
not limited to, vegetable oil, animal oil, insect oil, mineral oil,
esters, or other oil-soluble liquids. It also includes refined,
aromatic-free paraffinic and naphthenic oils, solvents, synthetic
liquids, hydrogenated or unhydrogenated oligomers of polybutene,
polypropylene, polydecene, and polyterpene. Other polyolefins also
are suitable.
[0051] A preferred mineral oil is white oil which is colorless and
transparent and generally is recognized as safe for contact with
human skin. Another preferred hydrocarbon oil is
poly-.alpha.-olefins ("PAOs"). The term "poly-.alpha.-olefin"
refers to a class of saturated olefin oligomers. A typical
poly-.alpha.-olefin includes various amounts of dimers, trimers,
tetramers, pentamers, hexamers of an .alpha.-olefin. A preferred
PAO is oligomers of 1-decene, although it may be oligomers of any
other .alpha.-olefins. Another preferred oil is hydrogenated
polyisobutene.
[0052] In some embodiments of the invention, the self-extinguishing
candle is formed by pressing a particulate candle base material
with a flame retardant in a mold. Such pressure molding may occur
at ambient or elevated temperatures, with the pressure causing the
candle base material particulates to meld into a solid unit.
[0053] The self-extinguishing candles in some embodiments employ
one or more wicks, typically of porous material which may be either
waxed or unwaxed and of the thickness and type appropriate for the
particular candle design. Any wick may be used. The wick or wicks
may include a decorative feature, for example, striping, coloring,
impregnation or coated with material for special effects, such as
to provide a colored flame, sparkles, etc., if so desired.
[0054] The self-extinguishing candles in accordance with
embodiments of the invention also may contain one or more additives
such as stabilizers, U.V. inhibitors, antioxidants, colorants,
fragrances, flame retardants, and the like to an extent not
adversely affecting or decreasing the desired properties of the
candle. Stabilizers and other suitable additives include, but are
not limited to, performance enhancing additives, materials which
improve the candle's burn properties, materials which improve the
candle's appearance, and the like to an extent not adversely
affecting or decreasing the desired properties of the candle. With
respect to antioxidants, specific reference is made to
2,6-di-tert-butyl-4-methylphenol known as "BHT," which is generally
employed at about 0.0 to about 1 weight percent. Other antioxidants
also may be used. These additives can be placed in the candle body,
the flame resistant block, or both.
[0055] Colorants may be added to the candles. The candles may be
multicolored or have colored layers. The latter is achieved by
forming one colored layer, allowing the layer to cool, and
overlaying with a second colored layer, and so on. Other designs
can be employed, such as single or multi-color swirls. Such swirls
can be achieved by adding the color to the candle base material at
a time during cooling of the composition but prior to complete
solidification, and gently stirring the composition. Still other
design variations are apparent to those skilled in the art.
[0056] In addition to colorants, ornamental features may be
embedded within the candle body, the flame resistant block, or
both. Such features may be either insoluble or soluble in the
respective composition of the candle, as desired. Use of such
ornamental features allows a possibility not heretofore available
in decorative features, as virtually any decorative object can be
incorporated within the candle body, provided generally that such
decorative feature does not adversely affect the burning capacity
of the candle in an undesired way.
[0057] Notwithstanding the above, decorative and other functional
features that interfere with the burning of the candle may be
incorporated, if so desired. For example, in suitable candle
designs, decorative features located near the periphery of the
candle and not in communication with the wick or flame will not
adversely affect the operation of the candle and may thus be of any
sort desired. Such a decorative feature may be placed in the
candle, for example, by addition to the candle base material after
sufficient cooling of the melt but before complete
solidification.
[0058] Exemplary decorative features include glitter, sparkles,
ribbons, air bubbles of various size, and other soluble, partially
soluble and insoluble embeds. A pearlizing agent may be used in the
candle. Other decorative additives, such as those that cause
special effects, e.g., sparkling, flame coloring, etc., or mixtures
thereof, also may be added to the candle base material of the
candle in effective amounts and as desired. In addition,
fluorescent and phosphorescent pigments or dyes may be added to
enhance the appearance of the candle. U.S. Pat. No. 6,433,068,
entitled "Hydrocarbon Gels as Suspending and Dispersing Agents and
Products," discloses a suspension system which can be used in
embodiments of the invention. The disclosure of this patent is
incorporated by reference in its entirety herein.
[0059] Fragrances, for example, cinnamon, spice, bayberry, pine,
essence oils, etc., also may be used in a manner similar to the way
wax candles employ pleasing aromatic additives. Any fragrances
soluble in or otherwise compatible with the candle composition may
be used in making the candles. These fragrances can be employed by
inclusion into the heated candle base material. Alternatively, if
the fragrance is particularly volatile, it is preferably added to
the cooling composition prior to complete solidification.
Fragrances are generally employed at up to about 20% by weight of
the total candle base material. However, it is recognized by those
skilled in the art that fragrant additives can be used up to their
characteristic solubility level in the composition of the
candle.
[0060] The self-extinguishing candles in accordance with
embodiments of the invention may further contain a functional
additive, such as an insect repellant, for use in the same capacity
as conventional candles containing such an additive. The flame
retardant may be present in amounts from about 0.01% to about 50%
by weight; more preferably from about 0.1% to about 35% by weight;
and most preferably from about 0.5% to about 10% by weight. For
example, U.S. Pat. No. 5,387,418 discloses one such insect
repellant compound that may be employed in the candles. The
disclosure of the patent is incorporated by reference herein in its
entirety. Citronella oil is another example of an insect repellant
that may be used in embodiments of the invention. These additives
are used in the conventional amounts as known in the art.
[0061] The following examples are presented to illustrate the
invention but are not to be considered as limiting the invention.
The following include examples of each of the three types of
self-extinguishing candles: (1) those in which the flame retardant
is evenly distributed throughout the candle; (2) those in which the
flame retardant is distributed as a gradient with a higher
distribution at the bottom of the candle; and (3) those in which
the flame retardant is present only in a lower portion of the
candle. The Kraton.RTM. polymers used in these examples were
obtained from Shell Chemical Company. FR 5914 and FR 5315, referred
to in the examples below, are paraffin waxes sold under the Bareco
trade name. Micro 195, a microcrystalline wax, was obtained from
Bareco, Vybar 103, Vybar 260, and Vybar 343 were obtained from
Baker Petrolite. Calprene H 6120P was obtained from Momentum
Technologies, Inc.
EXAMPLE 1
[0062] A candle base material of 69.9 grams FR 5914, 10 grams FR
5315, 10 grams white petrolatum, and 0.10 grams Kraton G1650. 0.1
grams of Aerosil R 972, a fumed silica composition, was added to
the candle base material and mixed. A candle was prepared with an
appropriately sized wick. The resulting candle was lit and the
flame self-extinguished after 6 minutes and 30 seconds.
EXAMPLE 2
[0063] A candle base material containing 70.5 grams Bareco FR 5315,
4 grams Micro 195, 3 grams Vybar 260, 10 grams Yellow Beeswax, 10
grams Soy Wax, and 1 grams Calprene H 6120P was prepared. 1.5 grams
talc was added to the candle base material and permitted to
partially settle such that there was a larger concentration of talc
at the bottom of the resulting candle than at the top of the
candle. The candle was lit and self-extinguished after 30 minutes
of burning.
EXAMPLE 3
[0064] A candle base material containing 66.9 grams Bareco FR 5914,
5 grams Bareco FR 5315, 15 grams white petrolatum, 3 grams Micro
195, 3 grams Stearic Acid, 4 grams Yellow Beeswax and 0.1 grams
Ajinomoto GP-1, was prepared. 3 grams bentonite clay was added to a
candle before hardening of the base material so as to obtain a
greater concentration of the clay at the bottom of the candle than
at the top of the candle. Ajinomoto GP-1 is a dibutyl lauroyl
glutamide compound. The candle was lit and self-extinguished after
8 minutes and 20 seconds.
EXAMPLE 4
[0065] A candle base material containing 56.2 grams Bareco FR 5914,
36.7 grams Bareco FR 5315 1.5 grams white petrolatum, 0.7 grams
Stearic Acid, 3.8 grams yellow beeswax, and 0.1 grams Kraton G1701
was prepared. 1 grams of fumed silica was added to the base
material. A candle was then prepared using an appropriate wick and
the resulting candle had substantially constant concentration of
the fumed silica throughout. The candle was lit and it burned with
a small flame. The candle self-extinguished after about 2
hours.
EXAMPLE 5
[0066] A candle base material containing 85.0 g Bareco FR 5914, 5.0
g Bareco FR 5315, 3.0 g Bareco Micro 195, 1.0 g Stearic Acid, and
1.0 g Yellow Beeswax was heated to 90.degree. C. with stirring. To
this mixture was added 2.0 g Kraton G1650 and 2.0 g Kraton G1702.
The blend was stirred until the polymers were dissolved and the
mixture was uniform and homogeneous. Aerosil R972 (1.0 g) was added
to the candle base material. A candle was prepared from this
material, with the Aerosil being uniformly distributed throughout
the candle. When the candle was lit, it self-extinguished after 1
minute and 30 seconds.
EXAMPLE 6
[0067] A candle base material containing 87.90 g Bareco FR 5914,
0.10 g Vybar 103, 3.00 g Stearic Acid, 1.00 g Kraton G1654, 1.00 g
Kraton GRP 6917, 2.00 g Kraton D1102, and 5.00 g Dow Corning 200
Silicone Fluid (350 cSt) was prepared and made into a candle. The
silicone fluid was evenly dispersed throughout the candle. When
lit, the candle burned steadily, with a small, controlled
flame.
EXAMPLE 7
[0068] A candle base material containing 76.0 g Bareco FR 5315, 5.0
g White Petrolatum, 10.0 g Bareco Micro 195, 8.0 g Kraton G1652,
and 1.0 g Stearyl Methicone was prepared. This was made into a
candle with the Stearyl Methicone being distributed evenly
throughout the candle. When lit, the candle had a steady burn, with
a very small flame.
EXAMPLE 8
[0069] A candle base material was prepared from 87.0 g Bareco FR
5914, 10.0 g White Petrolatum, and 2.0 g Bareco Micro 195. To the
bottom portion of this candle base material was added enough
Aerosil R972 to give a concentration of 1 wt %, while the top
portion of the candle contained no Aerosil R972. When this candle
was lit, it burned as a normal candle until the flame reached the
region of the candle which contained the Aerosil. At this point,
the candle self-extinguished and could not be re-lit.
EXAMPLE 9
[0070] A candle base material containing 85.0 g Bareco FR 5914, 3.0
g Bareco Micro 195, 1.0 g Stearic Acid, and 10.0 g Yellow Beeswax
was heated until melted. To this was added 1.0 g Aerosil R972. A
candle was prepared from this base, which self-extinguished after
burning for 2 minutes.
EXAMPLE 10
[0071] A candle base material containing 68.50 g Bareco FR 5914,
19.00 g Bareco FR 5315, 2.00 g White Petrolatum, 3.00 g Stearic
Acid, and 5.00 g Yellow Beeswax was heated until melted. To this
was added 2.50 g Aerosil R972. A candle was prepared from this
base, which self-extinguished after burning for 3 minutes.
EXAMPLE 11
[0072] A candle base material containing 81.20 g Bareco FR 5315,
5.00 g White Petrolatum, 10.00 g Bareco Micro 195, and 3.00 g
Kraton G1652 was mixed with heating until homogeneous. To this was
added 0.80 g Aluminum Oxide with stirring. This was made into a
candle, with uniform dispersion of the aluminum oxide throughout
the candle. When lit, the candle burned very slowly to completion,
with a very small flame.
EXAMPLE 12
[0073] A candle base material containing 86.70 g Bareco FR 5914,
0.30 g Vybar 103, 3.00 g Stearic Acid, and 5.00 g Kraton G1702 was
heated until all the solids had melted or dissolved. To this was
added 5.00 g Titanium Dioxide. A candle, with even dispersion of
the titanium dioxide, was prepared from this base. The candle was
lit, and it self-extinguished after 5 minutes.
EXAMPLE 13
[0074] A candle base material containing 90.0 g Soy Wax, 6.0 g
Bareco FR 5315, and 3.0 g Vybar 260, was prepared. To this was
added 1.0 g Aerosil R972 with mixing. This base, with
evenly-dispersed Aerosil, was made into a candle, which
self-extinguished 20 seconds after being lighted.
EXAMPLE 14
[0075] A candle base material containing 85.40 g Bareco FR 5315,
2.50 g Bareco Micro 195, 0.10 g Vybar 260, 6.00 g Yellow Beeswax,
and 4.00 g Kraton G1652 was heated with stirring until the mixture
was uniform and homogeneous. To this was added 2.00 g Bentonite
Clay. A candle, with uniform dispersion of the bentonite clay
throughout, was prepared from this base. The candle
self-extinguished after burning for 15 minutes.
EXAMPLE 15
[0076] A candle base material containing 51.00 g Bareco FR 5914,
4.00 g Bareco FR 5315, 15.00 g White Petrolatum, 3.00 g Bareco
Micro 195, 3.00 g Stearic Acid, 4.00 g Yellow Beeswax, 5.00 g Soy
Wax, and 5.00 g Kraton G1650 was heated with stirring until the
mixture was smooth and homogeneous. To this was added 10.00 g Talc,
with stirring. A candle, with even dispersion of the talc, was
prepared from this base. The candle was lit, and it
self-extinguished after 1 minute and 10 seconds.
[0077] A demonstrated above, embodiments of the invention provide a
self-extinguishing candle which may have one or more of the
following advantages. First, because the candle extinguishes
automatically after the candle base material is consumed by the
candle flame, there is little or no need for a candle extinguishing
device, such as a candle snuffer. The self-extinguishing feature of
the candle should provide some peace of mind to consumers. Also due
to its self-extinguishing feature, fire safety should improve.
Finally, due to its design simplicity, it is relatively cost
effective to manufacture the self-extinguishing candle. Other
advantages are apparent to a person of ordinary skill in the
art.
[0078] While the invention has been described with respect to a
number of embodiments, modifications and variations exist. For
example, instead of creating a single flame resistant portion in a
candle, multiple flame resistant regions may be used. The flame
resistant region need not be opaque; it can also be transparent or
translucent. Colorants may also be added to the flame resistant
region to enhance aesthetic appeal. The appended claims intend to
cover all such variations and modifications as fall within the
scope of the invention.
* * * * *