PURIFIED EXTRACT OF VIRGIN BEES-WAX AND PROCESS FOR ITS PREPARATION

Abstract: A purified extract of virgin bees-wax can be obtained by boiling the commercial bees-wax in water containing, if necessary, suitable amounts of borax and sodium chloride dissolved therein. The separation of a fair part of the unsaponifiable components is thus obtained with a weight loss of about one third compared with the weight of the treated wax. The obtained extract is particularly suitable to be used in cosmetic industry.

Description: ITS PREPARATION" The present invention relates to a purified extract of virgin bees-wax and a process for its preparation. Bees-wax, which is employed in the most different industrial fields, froa cosmetics to drugs, from candles to adhesives, from wax figures to casting moulds, from polishing waxes to paraffin paper, from textile sizings to chewing gum, etc., is produced by the diffe¬ rent species of bees (Apis Mellifica, Apis Dorsata, Apis Florea, Apis Indica and their subspecies) as well as by some wasps, and is formed by a more or less homogeneous mixture of components of different nature, such as resins, hydrocarbons, esters, saturated and unsaturated organic acids, alcohols, impurities of different kinds, etc. at least a half of which is unsaponifiable. Therefore, raw bees-wax is not suitable for the different uses above mentioned and even less for pharma¬ ceutical and cosmetic uses, for which a particularly homogeneous and purified wax is required. The raw wax is consequently submitted to refining and purification treataents, the most known of which are the treatments under pressure of the melted wax in the presence of water, those by means of steam, optionally in the presence of acids, as well as the bleaching process in the presence of oxidizing agents or adsorbing materials such as fuller's earth. However, these treatments merely aim at obtaining a wax more or less decolourized and free from the coarsest impurities; therefore, the thus obtained wax may still be not completely satisfactory for particular uses, such as those in pharmaceutical and cosmetic field, for which the absence of irritating and/or allergic phenomena is of utmost importance. The virgin bees-wax has a compact and partly granulous structure. The present invention lies in separating the compact part, i.e. t e extract, mainly made up of esters of bees-wax, from the granulous part, i.e. the by-product, mainly made up of the unsapo- nifiable fraction of bees-wax. The purpose of the present invention is, therefore, to obtain a purified "extract" of bees-wax having characterist cs concerning purity, homogeneity " and physicochemical behaviour decidedly superior than those commonly available on the market. The purified extract of bees-wax according to the present invention is obtained by treating the usual commercially available bees-wax in boiling water, if necessary in the presence of about 50% through 100% by weight, with respect to the wax, of a suitable inorganic salt, preferably sodium chloride and preferably also in the presence of 0,2-1,2% by weight, always with respect to the wax, of sodium tetraborate decahydra- te or of a corresponding amount of another suitable boric salt. Boiling is continued for a time approximate¬ ly ranging between 50 and 120 minutes at atmospheric pressure. The whole is then allowed to cool at room temperature and the extract of purified wax, solidified and floating on the aqueous solution, is taken away and, if necessary, cleaned up on the surface by lightly scraping the possible granulous parts, which could have remained attached to it. The amount of water employed for the just describ- ed treatment of bees-wax is not critical; there are however preferably used from about 7 to 12 liters of water per kilogram of wax. The weight of thus obtained extract of bees-wax corresponds to about 60-75% of the initially treated wax, while the remaining 25-40% by weight is represent¬ ed by the by-product, made up to a large extent of unsaponifiable products, gathered on the bottom of the treating vessel after solidification. The physicochemical characteristics of the bees wax extracts according to the invention usually range in the following limits: Melting point 62.67°C Specific gravity at 20°C 0.9660-0.9680 Refraction index (referred to 40°C) 1.450-1.510 Acidity number 17-29 Ester number 73-116 Saponification number 90-145 Iodine number 3-4.5 Ratio number ( NE/NA) 3.70-4.40 Hydroxyl number 47-126 Acetyl number 45-125 Unsaponifiable fraction 18-25% Without being bound to any hypothesis, we think that the extract of bees-wax according to the present invention derives from a complex de-emulsifying and hydrolysing reaction of some components of wax, with a loss of about two thirds of the unsaponifiable fract¬ ion, corresponding to a loss of about 25-40% by weight of the starting raw material, according to the quality, composition, age, origin of the bees-wax and to the species of bees which produced it, with a consequent concentration of the noblest part, mainly consisting of esters. The present invention will be now described in detail on the basis of some embodying examples given only for the purpose of illustration but not as a limitation. EXAMPLE.! 1 kg of .virgin bees-wax produced by Australian bees is vigorously boiled in a boiler containing 10 liters of water. 37 minutes later an impressive foaming can be seen, which causes an increase of several centi¬ meters of the level of the aqueous mass. Boiling is maintained for further 60 minutes during which a progres¬ sive fall and disappearance of the foam layer and an emulsifying of wax in water can be seen. At this stage, the content of the boiler is allow¬ ed to cool down to the room temperature, with the consequent separation of a cake of purified wax on the surface of the aqueous phase. The Lower surface of this cake, when separed, appears almost completely clean and only requires a very easy manual detaching of some clots of darker colour. At the end of the treatment the weight of the cake is 620 g, white the remaining part of the original kilogram of wax appears as a by-product, gathered on the bottom of the boiler as a granulous mass. The thus obtained wax extract appears as a solid, translu¬ cent, brightly yellow-coloured body, with a moderately hard consistency, clear-cut fracture and pleasant wax aroma. The sample of purified extract from virgin bees-wax obtained in Example 1 was analysed according to the methods usually followed in the analyses of waxes and the following results were obtained: Melting point 62-64°C Unsaponifiable fraction 19% Acetyl number 45.50 The 0/W and W/0 emulsions obtained by means of said extract are quite stable after eight months. The extract can be thoroughly homogenized with water, and the by-product, being absolutely free from foreign chemical substances, can be employed in wax mixtures or for other uses. IXANPLE.2 1 kg of virgin bees-wax produced by Apis Mellifica s- boiled in a boiler containing 10 liters of water, into which 800 g of sodium chloride have been dissolved and boiling is maintained for about one hour. The content of the boiler is then allowed to cool down to room temperature with the consequent separation of a cake of purified wax on the surface of the aqueous solution. The lower surface of this separated cake is cleaned from some residual attached clots. At the end of the treatment, the weight of the cake is equal to 754 g, while the remaining part of the original kilogram of wax appears as a by-product, gathered on the bottom of the boiler. The thus obtained wax extract appears as a solid, stiff, translucent, pale brown-yellow body, with a clear-cut fracture and pleasant wax aroma. EXAMPLE^ 1 kg of virgin bees-wax produced by Apis Mellifica is treated in the same way as in Example 1, with the difference that 500 g of sodium chloride and 6 g of monosodium tetraborate decahydrate (borax) are dissolv¬ ed in water. The thus obtained wax extract has a weight of 653 g and a pale strawy colour, thus being more transpa¬ rent than the product obtained in the previous Example. The sample of purified extract of virgin bees-wax obtained in Example 3 was submitted to analysis accord¬ ing to the methods usualy followed in the analysis of waxes and the following results were obtained: Melting point 65-67°C Specific gravity at 20°C (compared with water) 0.9675 Refraction index (reported at 40°) 1.455 Acidity number 28.68 Ester number 116.27 Saponification number 144.95 Unsaponifiable fraction 19.90% Iodine number 3.04 Ratio number CNE/NA) 4.36 Hydroxyl number 115.90 Acetyl number 106.63 In Figure 1 is reported the infra-red absorption spectrum of the product obtained according to Example 3 operating with a permanence time of 8 minutes, with a KBr tablet; in Figure 2 is reported the gas-chromat graphic spectrum of the acidic fraction; while in Figures 3a and 3b are reported the gas-chromatographic spectra of the extract of the unsaponifiable fraction of the same product in petroleum ether before purifica¬ tion and after purification through alumina. Upon examination of the R spectrum, the presence of compounds having a nature of alkyl esters is observ¬ ed. In the gas-chromatogram of the acidic fraction, performed after methylation of the free fatty acids, the presence of palmitic acid and of two further acids higher than oleic acid is observed. From the gas-chromatographic analysis of the ethereal extract of the unsaponifiable fraction in petroleum ether the presence of alcohols and hydrocarbons is observed, while it can be noticed that the purifica¬ tion through Al 0. has not caused remarkable modifica- tions, as it may be ascertained by comparing Figure 3a with Figure 3b. EXAMPl.E_4 1 kg of virgin bees-wax of different origin was treated in the same way as described in Example 3, thus obtaining 615 g of purified extract. The analysis of this extract gave the following results: Melting point 65-67°C Specific gravity at 18°C 0.9662 Acidity number 21.44 Ester number 80.90 Saponification number 102.34 Unsaponifiable fraction 18.91% Iodine number 4.22 Ratio number 3.77 Hydroxyl number 125.76 Acetyl number 124.5 Refraction index (at 40°C) 1.508 In conclusion, it can be stated that the extract obtained according to the process of the present invention shows, in comparison with any virgin commer- cial bees-wax, some remarkable modifications in the unsaponif able fraction, as well as in the values of the hydroxyl number and acetyl number. In this connection, for sake of comparison, a table summarizing the average chemical and physical characteristics of commercial bees-wax is given below. Melting point 61-66°C Specific gravity at 15°C 0.955-0.974 Refraction index at 40°C 1.4550-1.4590 Acidity number (NA) 17-22 Saponif cation number (NS) 86-100 Ester number (NE) 70-78 Ratio number (NR) 3.4-3.9 Iodine number (NI) .5-15 Hydroxyl number 15-16 Acetyl number 15-15.5 Unsaponifiable fraction 50-56% It must be noted that the remarkable differences that may be found among the above reported data are depending on the above mentioned parameters and parti- cularly on the different species and geographical locations of the producing bees. On the other hand this justifies the large ranges of the different process¬ ing data according to the present invention. Always in connection with the operative parameters according to the present invention, it can be pointed out that the mentioned boiling temperature must be understood at normal atmospheric pressure; however, this does not prevent from operating in different conditions, such as in autoclave under a moderate overpressure, which allows to increase the treatment temperature and, consequently, to shorten the boiling time. Another possibility is to operate, always at atmospheric pressure or under overpressure, by means of a compressed steam jet bubbling from the bottom of the processing vessel, which supplies an additional mixing up of the treated mass, with advantageous effects with respect to the separation of the desired product from the granulous part. Although the present invention has been illustrat¬ ed on the basis of some preferred embodiments, it is clear that some changes and/or modifications can be introduced by those skilled in the art without depart¬ ing from the spirit and scope of this invention.

Claims: CLAIMS 1. A process for preparing a purified bees-wax extract by heat treatment in water, characterized in that the wax is submitted to boiling in aqueous medium for a. time ranging between about 50 and 120 minutes and the floating layer of solidified extract is recover¬ ed after cooling as a compact body by separating the granulous by-product and the aqueous phase. 2. The process according to claims 1, characteriz¬ ed in that said aqueous medium is a solution of an inorganic salt. 3. The process according to claim 2, characteriz¬ ed in that said solution of inorganic salt contains also a small quantity of an alkali borate. 4. The process according to claim 3, characteriz- ed in that said aqueous solution contains an amount of said inorganic salt equal to about 50 to 100% by weight with respect to said wax and from 0,2 to 1,2% by weight of said alkali borate with respect to said wax. 5. The process according to claim 4, characterized in that said inorganic salt is sodium chloride and said alkali borate is monosodium tetraborate decahydra- te. 6. A purified extract of virgin bees-wax obtained according to the process described in any claim 1 to 5. 7. The purified extract of virgin bees-wax accord¬ ing to claim 6, characterized in that it has the follow¬ ing physico-chemical characteristics: Melting point 62-67°C Specific gravity at 20°C 0.9660-0.9680 Refraction index (referred to 40°C) 1.450-1.510 Acidity number 17-29 Ester number 73-116 Saponification number 90-145 Iodine number 3-4.5 Ratio number (NE/NA) 3.70-4.40 Hydroxyl number 47-126 Acetyl number 45-125 Unsaponifiable fraction 18-25% as well as the IR spectra in toto and gas-chromatographic spectra of the unsaponifiable fraction as shown in the enclosed figures.

Inventors: PAPPALETTERA LUIGI, PAPPALETTERA, LUIGI
Applicants: PAPPALETTERA LUIGI, PAPPALETTERA, LUIGI
Application year: 1987
Main classification: C11B3
IPC codes: A61K8, A61Q19, C11B3