EP1149888A1 - Application of fatty acidesters as illuminating oil - Google Patents

Abstract

Use of fatty acid esters containing linear and/or branched 6-14 C fatty acids and/or branched 6-10 C alcohols as luminous matter, grill igniter, lamp oil, gel-like candle and as a flare is new.

Description

Field of the Invention

The invention is in the field of lamps and relates to the use of Fatty acid esters containing linear and / or branched fatty acids with 6 to 14 carbon atoms and linear and / or branched alcohols with 6 to 10 carbon atoms as lamp oils, grill lighters, gel-like candles or torches.

State of the art

Lamp oils as well as petroleum, liquid lighters, gel-shaped candles or torches mainly contain paraffins as ingredients, which have been classified as dangerous and harmful to health due to their physico-chemical properties.
Soot development and the development of skin and eye irritating combustion products with a negative impact on the respiratory organs, particularly in the case of diseases of the bronchial system, sometimes go as far as triggering asthma attacks. Lung complications from accidental aspiration of fluorescent petroleum are also considered to be reasons for increasing concerns about lamp petroleum.
Under these circumstances, a search has often been made for substitutes for fluorescent petroleum which do not have the disadvantages mentioned above, but at the same time are economical in use and have a luminosity and effect comparable to petroleum.
The patent DE 197 16911 C1, for example, discloses the use of fat derivatives selected from the group comprising fatty acid glycerides, fatty acid esters, fatty alcohols and Guerbet alcohols with a solidification point below 0 ° C., an iodine number below 20 and a surface tension of more than 25 nM / m as lamp oils . The good flammability, ie low tendency towards Russians and the neutral odor, which was often disadvantageous in the case of animal or unsaturated, rancid fats, were guaranteed by the substitutes described, but the risk of health damage if swallowed remains. Young children often think that colorful and fragrant lamp oils are drinkable. The decorative lamps for decorative purposes are usually made of transparent glass, which means that the color and the fragrance make the oils appear particularly attractive and thus tempt you to eat them. According to current knowledge, toddlers mostly drink from unsecured oil lamps that are within easy reach. Therefore, the prescribed child-resistant closures and warnings on the refill containers do not offer adequate protection. Due to a very low viscosity, low surface tension and relatively low vapor pressure, the liquid can spread into the respiratory tract ("crawl into it") if swallowed and trigger severe chemical pneumonia there. Even if vomiting from swallowed lamp oil is triggered as a "detoxification measure", it can spread into the respiratory tract.

For children, even the smallest amounts (less than 1g = sucking on the wick) are enough trigger serious lung complications. The main symptom of poisoning is a immediate, persistent cough. Delayed vomiting and difficulty breathing can occur come. In severe cases, consequential damage can still be proven after 8 - 14 years and the Significantly reduce lung function.

In Germany, 130 cases were reported to the BgVV by the end of 1996. In three cases, the Poisoning to death, more than half of the cases were severe chemical Pneumonia registered, sometimes with serious further health problems. Therefore The EU recently issued new directives that require labeling.

Due to the new legal regulations, industry-wide potential substitutes were sought.
Then methyl esters based on rapeseed oil or coconut / palm kernel oil could be developed very quickly as an alternative. The published patent application DE 197 00 161 A1 also describes the use of fatty acid methyl esters or a mixture of fatty acid methyl esters as a replacement for fluorescent oil in oil lamps. In addition to the satisfactory product properties (viscosity, soot, resinification), the susceptibility to hydrolysis speaks against this product group:
After swallowing, an enzymatic / acidic cleavage can release methanol in the gastrointestinal tract, which has a very high toxicological potential.

The complex object of the present invention was therefore, while maintaining the good burning behavior to provide health-safe lamps that Ingestion does not cause pneumonia and no toxicological effects in the gastrointestinal tract Release questionable substances. At the same time, the lamp oils should be as low as possible Self-coloring and odor neutrality and based on renewable, vegetable Raw materials can be produced.

Description of the invention

The invention relates to the use of fatty acid esters containing linear and / or branched fatty acids with 6 to 14 carbon atoms and linear and / or branched alcohols with 6 up to 10 carbon atoms as illuminants.

Surprisingly, it was found that these fatty acid esters are accidentally present in the lungs, e.g. B. by swallowing, have a good tolerance. In addition to being better tolerated by health - so they do not release methanol when swallowed even in the presence of acid gastric juice - they still have good application properties. They burn with a soot-free flame, do not tend to resinify, are very user-friendly due to their low viscosity and, as a colorless to slightly yellowish and odorless liquid, can be easily adapted to buyers' wishes by adding fragrances and / or dyes.
While short-chain fatty acid esters have a strong intrinsic odor and long-chain unsuitable burning properties, such as strong soot, the range of 6 to 10 carbon atoms per alcohol and fatty acid is also suitable due to the viscosity of the fatty acid esters. With some fat derivatives, especially with triglycerides, such as olive oil, linseed oil, or also sesame oil, there is the problem of a strongly sooting flame, since the iodine number is above 20, and a very high viscosity.

Fatty acid esters

In the context of the present invention, fatty acid esters are understood to mean esters of the fatty acids listed in the formula (I) with linear or branched, saturated or unsaturated alcohols having 6 to 14 carbon atoms. However, esters of fatty acids with polyhydric alcohols can also be used. The esters of C ₆ to C ₁₀ fatty acids with C ₇ to C ₉ alcohols are preferred. Esters of C ₈ fatty acids with branched, unbranched, saturated or unsaturated C ₈ alcohols are particularly preferred. Suitable fatty acid components are, in particular, technical mixtures of fatty acids of the formula (I) and preferably the fatty acid cuts obtained from palm kernel and / or coconut oil. The use of esters from C ₈ fatty acids and C ₈ alcohols is preferred, and the use of 2-ethyl-1-hexyl octanoate (Edeno® LPL) is particularly preferred.

Fatty acids are to be understood as meaning aliphatic carboxylic acids of the formula (I) R ¹ CO-OH (I) in which R ¹ CO represents an aliphatic, linear or branched acyl radical having 6 to 14 carbon atoms and 0 and / or 1 or 2 double bonds.
Typical examples are caproic acid, caprylic acid, capric acid, lauric acid, myristic acid and their technical mixtures, which are obtained, for example, in the pressure splitting of natural fats and oils, in the reduction of aldehydes from Roelen's oxosynthesis or in the dimerization of unsaturated fatty acids. 2-Ethylhexanoic acid, iso-octanoic acids and n-octanoic acid are particularly preferred. The composition of the fatty acid mixtures in the particularly preferred fatty acid esters is: C ₆ - fatty acids <10% by weight C ₈ - fatty acids > 80% by weight C ₁₀ - fatty acids <10% by weight C ₁₂ - fatty acids <10% by weight C ₁₄ - fatty acids <10% by weight

Fatty alcohols are to be understood as primary aliphatic alcohols of the formula (II) R ¹ OH (II)

in which R ^{1 represents} an aliphatic, linear or branched hydrocarbon radical having 6 to 10 carbon atoms and 0 and / or 1 or 2 double bonds.
Typical examples are capronic alcohol, caprylic alcohol, capric alcohol, iso-octyl alcohol, iso-heptyl alcohol, iso-nonyl alcohol, iso-decyl alcohol, and their technical mixtures, which are used, for example, in the high-pressure hydrogenation of technical methyl esters based on fats and oils or aldehydes from the Roelen ' oxosynthesis and as a monomer fraction in the dimerization of unsaturated fatty alcohols. 2-Ethylhexanol, iso-octanol and n-octanol are particularly preferred. In terms of purity, the alcohol component of the fatty acid esters preferably contains at least 90% by weight, in particular at least 95% by weight, of C ₈ alcohols.
According to the invention, any mixtures of the fatty acids and alcohols listed can also be used. The components to be used according to the invention are preferably colorless and odorless.

Toxicological examinations on the lungs

An independent institute has developed a new method for the detection of the lung hazard potential in order to demonstrate the pulmonary safety of the fatty acid esters according to the invention when swallowed. The investigations were carried out on an in vitro model of the perfused lung [see also Uhlig, p. 1998, The isolated perfused lung. In: Methods in Pulmonary Research, S. Uhlig and AE Taylor, eds. Birkhäuser, Basel, CH, pp. 29-55; Uhlig, S., Held, HD, Göggel, R .; Applications of isolated perfused solutions; Pp. 41-54; 36 ^th Scientific Meeting (GV-Solas), Proceedings of a Workshop on Isolated Perfused Organs (Hamburg 1998)]. The technique of the isolated perfused lung includes the removal of the lungs from the thorax accompanied by extracorporeal perfusion through the pulmonary arteries and artificial ventilation. The lungs are kept alive for 8 hours under physiological conditions. Respiratory mechanisms, especially lung resistance and compliance, edema formation, gas exchange and vascular mechanisms are recorded and controlled.

method

HE 324 -

Handelsübliches Paraffinlampenöl (CRYSTAL Lampenöl, Batch-Nr.: B8166, Gottfried Schmalfuss, GmbH, Kerpen)

HE 372 -

Kokos/Palmkernmethylester (EDENOR® MEC12-70, Batch-Nr.: MV 989, Cognis Deutschland GmbH)

HE 384 -

C8/C8 Fettsäureester (EDENOR® LPL, Batch-Nr. 10059, Cognis Deutschland GmbH)

The investigations were carried out with three different dosage levels (2 µl, 10 µl and 25 µl). A conventional paraffin-based lamp oil, a methyl fatty acid ester with long-chain fatty acids and a C8 / C8 fatty acid ester (2-ethyl-1-hexyloctanoate) were used:

HE 324 -

Commercial paraffin lamp oil (CRYSTAL lamp oil, batch no .: B8166, Gottfried Schmalfuss, GmbH, Kerpen)

HE 372 -

Coconut / palm kernel methyl ester (EDENOR® MEC12-70, batch no .: MV 989, Cognis Deutschland GmbH)

HE 384 -

C8 / C8 fatty acid esters (EDENOR® LPL, batch no.10059, Cognis Deutschland GmbH)

After preparation from anesthetized 8-week-old Wistar rats, the lungs were perfused blood-free using pulmonary artery. The perfusion was carried out recirculating with Krebs-Henseleit buffer (37 ° C., 2% by weight albumin or 0.1% by weight homologous serum, 0.1% glucose, 0.3% HEPES, total volume 100 ml) at a constant hydrostatic pressure (12 cm H ₂ O) through the pulmonary artery, resulting in a perfusate flow rate of about 25 ml / min. The lungs were hung from the trachea and ventilated normally with 80 breaths / min and a breath volume between 1.6 and 2 ml. Every 5 min. a deep breath (sigh, 16 cm H ₂ O) was triggered. The pressure in the artificial thoracic chamber was measured with a differential pressure sensor (DP 45-14; Validyne Corp., Northride, CA, USA), the air flow rate (Validyne DP 45-15). Perfusate flow, arterial and venous pressure were continuously recorded. The pH of the perfusate was adjusted to 7.35. The lung weight was measured with the HSE LS30 weight sensor (Hugo Sachs Elektronik, March-Hugstetten, Germany).
The lungs were first perfused under control conditions for 30 minutes and ventilated with positive pressure. After 30 minutes, the lungs were briefly detached from the ventilator and, as a comparison, oil or saline were instilled into the lungs with a blunt cannula via the trachea. In order to better distribute the instillate in the lungs, the lungs were then ventilated with excess pressure for 5 minutes. The ventilation was then switched back to negative pressure ventilation for the rest of the experiment.

Results

The instillation of 10 µl saline or Mazola cooking oil carried out as a comparison had no influence on the lung functions examined. In contrast, instillation of 2 µl HE 324 (paraffin oil) or HE 372 (coconut / palm kernel methyl ester) led to a weight gain twice as observed in the controls (Table 1). If 10 µl or 25 µl was instilled by one of these two oils, this led to a dramatic deterioration in lung functions. The deterioration was so rapid that these lungs were completely edematous within 20 minutes. As soon as foam emerged from the trachea, the experiment was stopped. Therefore, a higher toxicity of the oils does not necessarily show in a larger weight gain, but rather in the fact that the maximum weight was reached more quickly. The instillation of C8 / C8 fatty acid esters always resulted in less weight gain than the other two oils. At a dose of 2 µl, the weight gain did not differ from that in controls. Weight gain 20 min. after oil instillation, the minimum compliance and the minimum airway conductivity (conductance) oil Number of attempts (amount of oil) Weight gain after 20 min [g] Minimal compliance [ml cmH ₂ O ^-1 ] Minimal conductance [ml cmH ₂ O ^-1 s ^-1 ] Control (saline or 4 (10 µl) 0.17 ± 0.07 0.27 ± 0.05 3.43 ± 0.16 Mazola cooking oil) HE 324 (paraffin oil) 3 (2 µl) 0.26 ± 0.09 0.24 ± 0.17 2.99 ± 1.25 3 (10 µl) 0.99 ± 0.56 0 ± 0 0. ± .0 3 (25 µl) 1.34 ± 0.54 0 ± 0 0 ± 0 HE 384 4 (2 µl) 0.13 ± 0.06 0.27 ± 0.14 3.49 ± 0.18 (C8 / C8 fatty acid ester) 4 (10 µl) 0.40 ± 0.20 0.27 ± 0.14 3.61 ± 1.22 5 (25 µl) 0.69 ± 0.35 0.10 ± 0.09 0.79 ± 0.72 HE 372 3 (2 µl) 0.38 ± 0.03 0.21 ± 0.04 3.20 ± 0.18 (Coconut / palm kernel methyl ester) 3 (10 µl) 1.39 ± 0.16 0.09 ± 0.16 1.13 ± 1.95 3 (25 µl) 1.34 ± 0.46 0 ± 0 0 ± 0

Figure 1 shows the dose-response curves as they would be for 20 minutes of weight gain. after administration of the oils. It can be seen that the ester (HE 384) according to the invention is less toxic than the other oils at all three doses investigated. The EC ₅₀ values show that HE 384 is about 5 times less toxic than the commercially available paraffin oil (HE324) (Table 1). Log EC ₅₀ values for the oil-induced edema formation of the three oils examined with standard errors oil Log EC ₅₀ [µl] HE 372 (coconut / palm kernel methyl ester) 0.49 ± 0.15 HE 324 (paraffin oil) 0.84 ± 0.20 HE 384 (C8 / C8 fatty acid ester) 1.52 ± 0.22

The edema formation (weight gain of the lungs) is the most sensitive parameter for the through Damage caused by lamp oil. Nevertheless, the conductivity of the airways (pulmonary conductance, the reciprocal of breathing resistance) and lung compliance examined also turn out best for the fatty acid esters according to the invention.

Studies on skin and mucous membrane compatibility

Furthermore, the skin and mucous membrane compatibility of conventional paraffin lamp oil (HE 324) against the ester according to the invention (HE 384) was investigated on the Bovine Udder Skin Model (BUS model). The tolerance of substances, mainly cosmetics, to the skin and mucous membranes is tested on cattle udders. The vascular system of a cattle udder pretreated in the slaughterhouse is connected in the laboratory to a perfusion unit of conventional transplantation medicine. The udder, including the skin and mucous membrane of the udder, is kept alive for at least 8 hours under physiological conditions using a nutrient solution. Biochemical and physical control ensures viability. Irritation and penetration into the skin can be observed and measured under realistic conditions [cf. also Pittermann WF, Förster, Th., Schmitt, M., Kietzmann M .; The Bovine Udder system (BUS-model) in cosmetic research; Pp. 13-15; 36 ^th Scientific Meeting (GV-Solas), Proceedings of a Workshop on Isolated Perfused Organs (Hamburg 1998)].
The skin tolerance after half-hour exposure with open application was good for both substances. The tolerance to the mucous membranes is equally good for both substances (exposure 0.5 h, semi-occlusive application).

Industrial applicability

The fatty acid esters according to the invention can be used as lamps, including conventional lamp oils which are used in wick, nozzle and evaporator devices, use gel-like candles, torches or liquid and solid grill lighters. Depending on the viscosity of the respective application, the fatty acid esters are adjusted by adding thickeners or materials are impregnated with the corresponding esters.
Fragrances and dyes can be incorporated very well, since the fatty acid esters have an extremely low intrinsic odor. Furthermore, they have good color stability even at elevated temperatures and they burn without residue.

Thickener

Suitable thickeners are, for example, polysaccharides, in particular xanthan gum, guar guar, Agar-agar, alginates and tyloses, carboxymethyl cellulose and hydroxyethyl cellulose, furthermore higher molecular weight Polyethylene glycol mono- and diesters of fatty acids, polyacrylates, (e.g. Carbopole® from Goodrich or Synthalene® from Sigma), polyacrylamides, polyvinyl alcohol and polyvinylpyrrolidone, Surfactants such as ethoxylated fatty acid glycerides, esters of fatty acids with polyols such as for example pentaerythritol or trimethylolpropane, fatty alcohol ethoxylates with restricted Homolog distribution or alkyl oligoglucosides. Polypropylene glycol is particularly preferred as Thickeners used. The thickeners can be used in an amount of 0 to 25, preferably 5 to 20 wt .-%, based on the fat derivative, are used.

Fragrances

As fragrances for the manufacture of lamp oils and / or grill lighters with various Fragrance notes can be used for perfume oils. The extracts may be mentioned as examples of perfume oils of flowers (lavender, roses, jasmine, neroli), stems and leaves (geranium, patchouli, petitgrain), Fruits (anise, coriander, caraway, juniper), fruit peel (bergamot, lemon, oranges), Roots (Macis, Angelica, Celery, Cardamom, Costus, Iris, Calmus), Woods (Sandal, Guaiac, Cedarwood, rosewood), herbs and grasses (tarragon, lemongrass, sage, thyme), needles and Twigs (spruce, fir, pine, mountain pine), resins and balsams (galbanum, elemi, benzoin, myrrh, Olibanum, opoponax). Animal raw materials such as musk, Civet and Castoreum. Ambroxan, eugenol, synthetic or semi-synthetic perfume oils are Isoeugenol, citronellal, hydroxycitronellal, geraniol, citronellol, geranyl acetate, citral, lonon and Methyl ionone into consideration.

In addition, fragrances can be used, as they already exist in GB 0001679 from 1855 are described.

Dyes

The dyes which can be used are those substances which are suitable and approved for cosmetic purposes, as compiled, for example, in the publication "Cosmetic Dyes" by the Dye Commission of the German Research Foundation, Verlag Chemie, Weinheim, 1984, pp . 81-106 . These dyes are usually used in concentrations of 0.001 to 0.1% by weight, based on the mixture as a whole.

Claims (12)

Use of fatty acid esters containing linear and / or branched fatty acids with 6 to 14 Carbon atoms and linear and / or branched alcohols with 6 to 10 carbon atoms as Illuminant. Use of fatty acid esters according to claim 1 containing linear and / or branched Fatty acids with 6 to 14 carbon atoms and fatty alcohols with 6 to 10 carbon atoms as Grill lighter. Use of fatty acid esters according to claim 1 containing linear and / or branched Fatty acids with 6 to 14 carbon atoms and fatty alcohols with 6 to 10 carbon atoms as Lamp oil. Use of fatty acid esters according to claim 1 containing linear and / or branched Fatty acids with 6 to 14 carbon atoms and fatty alcohols with 6 to 10 carbon atoms as gel-like candles. Use of fatty acid esters according to claim 1 containing linear and / or branched Fatty acids with 6 to 14 carbon atoms and fatty alcohols with 6 to 10 carbon atoms as Torches. Use according to one of Claims 1 to 5, characterized in that the acyl component of the fatty acid esters is derived to at least 80% by weight from fatty acids with 6 to 10 carbon atoms. Use according to one of Claims 1 to 6, characterized in that the acyl component of the fatty acid esters is derived to at least 80% by weight from fatty acids with 8 carbon atoms. Use according to one of claims 1 to 7, characterized in that the acyl component of the fatty acid esters is composed of at least 80% by weight of 2-ethylhexanoic acid or n-octanoic acid. Use according to one of claims 1 to 8, characterized in that the alcohol component of the fatty acid esters derives at least 90% by weight from alcohols with 8 carbon atoms. Use according to one of claims 1 to 9, characterized in that the alcohol component of the fatty acid esters derives at least 90% by weight from alcohols which are selected from the group formed by iso-octanol, n-octanol and 2-ethyl -Hexanol. Use according to one of Claims 1 to 10, characterized in that the fatty acid esters are 2-ethyl-1-hexyl octanoate. Use according to one of claims 1 to 11, characterized in that the fatty acid esters are used together with thickeners and / or colors and / or fragrances.

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