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POL MERIZED \\ AX CANDLES
TECHNICAL FIELD
Candles compnsing a w ax base and a copolymei of synthetic thermoplastic rubber copohmer additix es are disclosed The copolymer additix e is useful for binding excess oil w ithin the candle thereby allowing for the production of quality candles from less expensiv e base w ax Methods of manufacturing candles comprising a ax base and a copolymer of synthetic thermoplastic rubber additiv es are also disclosed.
BACKGROUND OF THE RELATED ART
Candles
e long since been used as an accepted method of
ing light, heat, scent, or for celebration or \ oti\ e purposes. Candles made from a ariety of w ax bases are well known w ithin the art. Typically, a wax base is dem ed from petroleum sources, vegetable sources, animal sources, synthetic sources, or some mixture thereof. The wax materials of candles are typically of high quality having a low amount oil therein A low amount of oil within the candle is associated with a high quality candle
Despite the low costs of using crude wax as a w ax base, high quality candles produced from crude w ax are expensiv e because the crude wax must be refined into higher quality w ax During the refining process, a crude wax, which ma> include as much as 20% oil is heated to drive off the oil. The process of driv ing off the oil also consumes some of the ax Therefore, a large amount of crude w ax is required to obtain a small amount of high quality wax. The large amounts of crude wax and the high costs of refining that crude w ax dπve up the costs of producing high quality candles
Due to the low costs of crude wax. it would be desirous to devise a method of producing high quality candles using crude ax To do this, it is necessary to determine alternate methods of binding or otherwise disposing of the oil that is inherent in crude ax. Currently, no methods, other than expensive refining processes, are a ailable to remove the oil from crude wax.
SUMM ARY OF THE DISCLOSURE
In satisfaction of the aforenoted needs, an economic method of binding the oil that is inherent w ithin a crude w ax or economical w ax source is disclosed The oi I within the crude w ax is economically bound through the use of a copolymei additi e By adding this copolvmer to crude w ax. high quality candles can be produced using less expensiv e crude ax as a starting material
The copolymer additiv e w hich is based on synthetic thermoplastic rubbers may be diblock, tπblock. radial block or a combination thereof Copolymers of this type are well known, and are typically used as adhesives, sealants and coatings For example, synthetic thermoplastic rubber copolymers produced under the tradename KRATON® are used in a v ariety of env ironments
A candle utilizing a w ax base and a synthetic thermoplastic rubber copolymer is also disclosed The wax base may come from economical sources such as petroleum sources, vegetable sources, animal sources, synthetic sources or mixtures thereof Further, the wax base may or may not be classified as a "crude wax" The copolymer used in conjunction w ith the candle may be a diblock, tπblock, radial block, or combinations of diblock, tπblock and radial block copolymers The addition of the copolymer to the ax base binds the oil within the wax, thereby permitting the production of candles w ith more cost effectiv e mateπals It is therefore an object of the invention to prepare candles with lower cost waxes which are presently unable to be used in candle-making preparation
One of the lo er cost waxes that are presently not useful in the candle making process are low-melt w axes Despite their lower cost, these low-melt waxes are not used prevalently because thev may melt during shipping during hot months. The addition of the copolymer stabilizes these low-melt waxes, by raising the melt temperature Thus, if low -melt waxes are used, the concern over melting during shipping is obviated by the addition of the copolymer according to the invention As an additional method of cost savings, candles produced according to this invention reduce processing times and percent defects Moreover, the candles can be
pioduced using standard candle manufacturing facilities Λs such it is an object ot this in ention to produce candles utilizing an optimized manufacturing process
In addition to the cost sav ing benefits, the addition of the copolv mer has been found to alter the crystalline structure of the w ax bases thereby allow ing for the manipulation of the bum rate of the candles The bum rate manipulation is achiev ed because the altered crystalline structure prov ides multiple temperature gradients throughout the candle It is therefore an object ot the inv ention to prov ide candles that hav e longer bum times than conv entional candles In addition to longer bum times, the multiple temperature gradients of the candle prov ides safety benefits by prev enting spillovers because the edges of the candle are substantially cooler than the center pool
Finally, the disclosed candles are useful for suspending a vaπety of safety and aesthetic additives For example, flame retardants can be suspended to extinguish the candle at the desired point Glitter and other aesthetic additives may also be suspended in the candle DETAILED DESCRJPTION OF THE
PRESENTLY PREFERRED EMBODIMENTS
A candle made of a composition hav ing a w ax source and a thermoplastic copolymer is disclosed The copolymer is present in an amount of ranging from about 0 125% by weight to about 10% bv weight Preferably, the copolymer is present in an amount ranging from about 0 25% by w eight to about 2% by weight
The copolymer is based on s nthetic thermoplastic rubbers, and may be diblock, tπblock, radial block or a combination of the three The synthetic thermoplastic rubbers hich are produced under the KRATON® tradename are useful in this invention The Kraton E rubber polymers, which are produced by the Shell Chemical Company, are elastomers w ith a high strength and low viscosity
Additionally, KRATON® has a unique molecular structure of linear diblock, tπblock or radial polymers. Each molecule of the KRATON® rubber is believed to consist of block segments of styrene monomer units and rubber monomer units and each block segment may consist of 100 monomer units or more The most common structure is the linear ABA block type, styrene-butadiene-styrene (SBS) and styrene-isoprene- styrene (SIS), the KRATON f D series A second generation polymer of this seπes is the KRATON® G seπes which are styrene-ethylene-butylene- styrene type (S-EB-S)
polv mers Diblock polvmers include the AB A tv pe and the SB stv rene- ethv lcnepropylene (S-EP) and (S-EB) The AG A stiuctuie of the KR ATON S rubber molecule has polystyrene endblocks and elastomeπc midbloc s This series of polv mers is sold commercially and indicated as being maioi compounding ingredients oi additiv es in adhesiv es sealants and coatings, asphalt modifications for roads and roofing, polymers modification, thermoset modification and oil modification including use as viscosity index improv ers greases and gels The KRATON® G rubbers are indicated as being compatible w ith paraffinic and naphthionic oils and the ti iblock copolymers are reported as taking up more than 20 times their w eight in oil to make a product which can v ary in consistency from a "Jello ' to a string elastic rubbery mateπal depending on the grad and concentration of the rubber
The ability of a synthetic thermoplastic rubber copolymer to bind oil allows for the use of inexpensive alternatives for the fuel source or w ax base For example, in the case of paraffinic waxes, instead of using wax that has had all of the oil burned off through the expensive refining process, the inexpensiv e "slack wax" can be used.
Normally, the use of "slack wax" would not produce a candle of suitable quality because of the oil present therein However, by blending the "slack wax" with the appropriate amount of the synthetic thermoplastic rubber copolymer, the oil is bound Thus, a high quality candle can be produced from a relativ ely inexpensive wax source
Moreover, the addition of the synthetic thermoplastic rubber to a wax base of a candle improves the shipping characteristics of the candle Often, candles that are prepared with a lower quality w ax are damaged bv heat during hot shipping months This problem is overcome in candles that utilize the synthetic thermoplastic rubber copolvmer according to the invention The reason for this is that the copolymer actually works to raise the melt temperature of the wax base As such, the addition of the copolymer to a wax base reduces the concerns of shipping candles in hot months The wax base used in the candle composition is a fuel source The wax base may come from a vaπety of sources For example, the wax base may be made from petroleum sources, vegetable matter, animal-fat matter, synthetic matter, or a combination thereof Other sources may also be used so long as they are useful as a
fuel source Preferably. , the w ax base is present in the candle composition in an amount greater than 50 peice t bv eight
The candle composition may also include other additiv es such as fragrances, stabilizers, dyes and hydrocarbon oil Fragrances mav be added in an amount up to about 10 w eight percent Stabilizers mav be added in an amount of up to 1 percent bv w eight Dyes may be added in an amount of up to 2 percent by weight Finally, hydrocarbon oil may be added in an amount of up to 10 percent by w eight
Candles prepared from compositions according to this disclosure are made in a conv entional manner The candles w ill include a body poπion and at least one w ick that is disposed w ithin the body Depending on manufacturing capabilities, the body of the candle may be formed in a v aπety of different shapes and sizes Additionally, multiple w icks may be found within the candle
Bu testing of candles made in accordance with this disclosure rev eals that the addition of the synthetic thermoplastic copolymer to the wax base alters the crystalline structure of the wax base thereby allowing for dynamic and unexpected bum characteπstics One such characteπstic is revealed by thermal photography. When candles are lit. they typically produce a wax pool in the area immediately adjacent the wick The liquefied wax that becomes the fuel for the candle to maintain its flame Thermal photography reveals that candles that are not produced according to the in ention demonstrate sharp temperature gradients For example, when lit, the area immediately adjacent to the wick can bum at temperatures up to 176°F The next temperature gradient drops sharply to 140°F This sharp temperature drop may cause the size of the wax pool to rapidly expand radially This may lead to the dangerous situation of wax spillover Candles produced according to the disclosure, however, minimize the πsk of spillover because the addition of the synthetic thermoplastic copolymer alters the crystalline structure of the wax base thereby allowing for a much smoother temperature gradient transition within the candle This gradual temperature reduces the probabilities of wax spillovers because a natural well is formed for the wax to settle in One method of prepaπng begins by heating the wax base to a temperature w ithin the range 170°F to 220°F After heating, the copolymer additive is mixed in
for 30 minutes or until homogeneous I pon the completion of mixing, the batch is cooled to 170"F, w hereupon the desired additiv es, such as stabilizers, dy es, hydrocarbon oils, fragrances, etc.. can be added. After the addition of the additi es, the entire composition should again be mixed until it is homogeneous. Preparation of the candles is completed w hen the composition is poured into molds at 1 70" F
An alternativ e method of preparing candles includes the initial step of preparing a copolymer pre-mix in lieu of mixing the full amount of copoly mer into the full amount of w ax base Tins pre-mix may contain from about 1 % to about 49% by w eight copolymer. and about 51 % to about 99% wax base. Due to the fact that the v iscosity of the copolymer pre-mix is directly related to the amount of copoly mer present, it is preferable to use a pre-mix containing from about 8% to about 12% by weight copolymer. and about S8% to about 92% wax base. The pre-mix is prepared by first heating the requisite amount of wax base to a temperature within the range of about 190°F to about 220°F. After heating the wax, the next step is to add in half of the copolymer. That composition is then mixed until the copolymer is in solution.
The remaining copolymer is then added in and mixed until the entire solution is homogeneous.
Preparation of the final candle composition using the copolymer pre-mix is very similar to the preparation without the copolymer pre-mix. The only difference is that instead of mixing the copolymer into the heated wax base directly, the copolymer pre-mix is added to the heated wax base. Thus, the first step is to heat the w ax base to a temperature within the range of about 170°F to about 220°F. After heating, the copolymer pre-mix is mixed in for 30 minutes or until homogeneous. Upon the completion of mixing, the batch is cooled to 170°F, whereupon the desired additives, such as stabilizers, dyes, hydrocarbon oils, fragrances, etc., can be added. After the addition of the additives, the entire composition should again be mixed until it is homogeneous. Preparation of the candles is completed when the composition is poured into molds at 170°F.
The aforementioned preparation methods can be employed using standard candle manufacturing facilities. Moreover, candles produced according to the invention reduce processing times and percent defects. These added benefits work to
further reduce the costs of pioducmg candles
EXAMPLE 1 A candle hav ing a w ax base made from petroleum matter w as prepared in accordance with the described protocol The w ax base is about 78 75% by w eight of the candle composition Paraffin w ax sold by Exxon Mobil under the trade name Pan an 129 and micro-cry stalhne w ax sold by Bareco Products under the trade name Be SquareS are examples of the types of petroleum matter that may be used to prepare the wax base according to this example The synthetic thermoplastic rubber copolymer used in this example is a styrene-ethylene-styrene block copolymer. Sold by Shell Chemical Company under the tradename KRATON® 1652, the synthetic thermoplastic rubber copolymer is present in an amount of about 5% by eight Additionally, steaπc acid, sold under the tradename Emersol® 7036 by the Cognis Company, may be present in an amount of about 1% by weight Other polymers, such as polyethylene sold under the trade name Vybar® 103 by Baker-Petro te is also present in an amount of 1 % by w eight Finally, fragrances and dyes can also present For example, fragrances such as coconut creme sold by J. Manheimer may be present in an amount of about 5% by weight Similarly, a dye such as Nitro Fast Blue 2B Powder, sold by the Claπant Corporation, may be present in an amount of about 0 25% by weight
EXAMPLE 2 A candle with a wax base made from v egetable matter is prepared in accordance with the described protocol The w ax base is present in an amount of about 99%o by weight, and may be vegetable fatty acids, soybean wax, beeswax or other vegetable based sources Additionally, a synthetic thermoplastic copolymer such as styrene-ethylene-styrene block copolymer, is also present in an amount of about 1% by weight. KRATON β 1652 sold by the Shell Chemical Company is a suitable example of such a copolymer
EXAMPLE 3
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A candle w ith a wax base made fiom animal-fat mattei is prepared in accoidance w ith the described protocol The wax base is piesent in an amount of about 98% by w eight Suitable animal-fat sources include tallow base fatty acids Additionally, a synthetic thermoplastic copoly mer such as KRATON S 1652 is also piesent in an amount of about 2% by w eight
EXAMPLE 4 A candle with a w ax base made from synthetic matter is prepared in accordance w ith the descπbed protocol The wax base is present in an amount of about 92% by weight. The synthetic sources that may be used as a wax base include, among others, synthetic paraffin w axes such as Calhsta 122 made by the Shell Chemical Company, and alpha olefins Additionally, a synthetic thermoplastic copolymer such as KRATON® 1652 is also present in an amount of about 8% by eight
EXAMPLE 5 A candle with a wax base made from a mixture of vegetable and petroleum matter is prepared in accordance with the described protocol The wax base is made of about 55% vegetable matter such as soy and about 45% petroleum matter such as paraffin. The wax base makes up about 99% of the candle composition. The remaining about 1% is made up of a sy nthetic thermoplastic copolymer such as KRATON® 1652.
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein w ithout departing from the spirit and scope thereof.