DE19849514C2 - Sunscreens - Google Patents

Description

The invention relates to a sunscreen. The basic problem is increasing stronger solar radiation on the earth's surface due to various influences and the result is an increased exposure to UVA and UVB radiation in general known. In this context, recognized dermatologists worldwide postu lates that protection against the two UV radiation spectra also increases the risk of Acquisition of a malignant skin disease, such as melanoma, is minimized becomes. A necessary high protection factor is practically only through the Kombinati on organic chemical with microfine mineral pigments, because the use of only chemical absorbers without mineral reflecting agents so high usage concentration tion would cause the risk of allergic and sensitizing effects ex increased proportionally. It should also be borne in mind that, according to recent studies, the Re sorption through the skin is a not insignificant systemic load on the body pers conditioned with the protective substances; here too the effect increases with increasing sub punch concentration very strongly.

A wide variety of recipe components for the formation of suns are available on the market protection means offered. The formulation components concern waxes, fats, oils, on the other hand moisturizer, UV filter and reflective agent, as well as emulsifier Ren, skin care substances, perfume oils and preservatives.

DE 197 16 070 A1 relates to chitosans as a new ingredient for sun protection medium. The chitosan group of substances is said to have a stabilizing effect on emulsions. Affected are therefore only preparations with chitosans as an ingredient. In addition, in DE 197 16 070 A1 textbook or catalog-like all potential ingredients or only groups of substances for sunscreens that are currently known are listed. This also includes questionable or obsolete ingredients. A consideration or to The usability or combinability of such ingredients is also not given such as the assessment of galenic, pharmacological, toxicological or dermatolo properties. With regard to the sunscreen according to the invention Cocoglycerides, Benzophenone-3, Titanium dioxide and Cyclomethicone mentioned by name. The remaining ingredients can only be found with a more or less exact naming of the generic term mention.  

The US 57 33 531 A relates to the use of microencapsulated organic or inorganic UV absorbers or reflectors. Here, too, the list is diverse known ingredients that can be microencapsulated. EP 08 95 775 A1 sets Production process for coated inorganic pigments, known orga African UV absorbers by melting onto the inorganic components be brought. There are in turn a multitude of substances and substance groups listed. In US 57 33 531 A and EP 08 95 775 A1 production processes for mo shown different ingredients. Known UV protection substances become so changed that the use of galenic modifications facilitates the use or by the Ver Binding two known components to a new compound active ingredient workability is facilitated.

From Chem. Abstr. 124: 185099j (1996) and Chem. Abstr. 118: 154080t (1993) is removable, Use titanium dioxide in sunscreens.

The invention has for its object to design a sunscreen in such a way that Achieved high UVA and UVB protection in a cost-effective and skin-friendly manner becomes.

This object is achieved by a sunscreen with the features of single claim solved.

The advantages of the invention are that, despite dermatological safety and a low sun protection factor is achieved at low cost. Cocoglycerides is a coconut Oil derivative, which has a rather slow to medium spreading ability. It owns the egg property, the UV filter complex of benzophenone-3 used to an outstanding degree and solubilize isoamyl p-methoxycinnamate so that one compared to others In addition to the higher galenic stability, the oil also decreases when the tendency to crystallize decreases Larger sun protection factors of the overall preparation with otherwise the same filter content achieved. Cocoglycerides lies in an emulsion as an extremely finely divided fat with a small trope size and high degree of dispersion; this circumstance also galenically supports the high filter presentation on the skin and thus increases the sun protection effect of the preparation tung. Isoamyl p-methoxycinnamate has good UVB protection. It also represents  Isoamyl p-methoxycinnamate is an excellent solvent for the Benzophe UV filter none-3. Benzophenone-3 has both UVA and UVB protective properties. Although benzophenone-3 is not problematic galenically, since this substance in water is insoluble and at least sparingly soluble in most lipids, solubilization succeeds tion with the aforementioned components cocoglycerides and isoamyl p-methoxycinna mate as stated earlier. To the by a filter substance dissolved in the water phase Phenylbenzimidazole Sul will improve the sun protection effect of the overall preparation fonic acid used. Phenylbenzimidazole Sulfonic Acid is a water-insoluble acid represents, which is converted with tromethamine in their salt and thus in the water-soluble form. At the same time, tromethamine has a buffering effect and can therefore last longer Ensure maintenance of the neutral pH without changing the formulation as a precautionary measure, it would have to be adjusted to non-physiological, i.e. alkaline, to prevent the association and thus recrystallization of the sulfonic acid. In process tromethamine has the advantage of a short production time of the water phase, since no gaseous reaction products are formed.

In order to be able to reduce the concentration of chemical UV filter substances and at the same time as the more important for the protective effect of the overall preparation seen UVA protection, a titanium oxide is used as a reflection agent, the blended or coated with dimethicone and aluminum oxide. This refinement components cause an ambiphibia of the pigment, so that a dispersion in water and oil is equally possible.

This optimal wettability reduces the tendency to whiteness in a water-in-oil emulsion, which is already comparatively low due to the micronization. The photocatalytic The activity of the pigment used is low.

In summary, it works through the synergism of the four filter substances, at niedi substance concentrations and thus lower resorptive load on the user, maintain a high degree of protection in the entire UVA and UVB spectral range; the kos metallic product properties are nevertheless very good and there is no whitening.  

The emulsifier system is based on two dodecyl glycol copolymers, one of which as a real emulsifier, the other serves as an emulsion stabilizer and coemulsifier. Both Dodecyl glycol copolymers belong to the group of polyalkylene glycols and represent what water-in-oil emulsifiers or stabilizers of such emulsions. The water-in In contrast to an oil-in-water emulsion, oil emulsions promote whitening Do not apply cream on contact with water, as you reduce the whitening due to the reduced wettability of the pigment is suppressed with water. Water-in-oil preparation is also easier formulated permanently waterproof. Due to the hydrophobicity obtained, the waste reduced formulation and increased skin adhesion. This requires a small one re necessity of repeat application even when exposed to water and sweat.

With regard to the fat phase, oleyl erucate, dicaprylyl ether and cyclomethicone are used applies. With the above-mentioned components, the fat phase is achieved slowly, includes medium-strength and fast-spreading oils. This mixture creates a long lasting the feeling of smoothness felt from the start. If the composition of the Fat phase, the preparation can be a greasy, sticky or non-caring one leave pressure that has a negative impact on compliance. Oleyl Erucate is hiring synthetic jojoba wax and has a slow spreading ability. Yet it is quickly absorbed, is very affinity for the skin and leaves a high impression of care. di caprylyl ether is a fast-spreading ether and can be classified as a so-called dry oil fen. The viscosity is water-like and it leaves no noticeable fat on the skin Movie. Cyclomethicone has similar sensory properties as dicaprylyl ether. It leaves no feeling of fat on the skin and serves to increase the water resistance of the skin Total preparation.

An embodiment of the invention is described in more detail below.

Composition of a sunscreen, whereby the stated weight percent may be slightly below or exceeded:
8.0% by weight cocoglycerides,
6.0 percent by weight oleyl erucate,
4.0 weight percent dicaprylyl ether,
3.0% by weight hydrogenated castor oil,
2.0% by weight of methyl palmitate,
1.0% by weight cyclomethicone,
3.0 weight percent glycerols,
4.0% by weight of isoamyl p-methoxycinnamate,
2.0 percent by weight benzophenone-3,
2.0 percent by weight of phenylbenzimidazole sulfonic acid,
4.0% by weight titanium dioxide with alumina and with dimethicone as a solid mixed product or blend,
3.0 weight percent PEG 45- / dodecyl glycol copolymer,
3.0 weight percent methoxy PEG-22 / dodecyl glycol copolymer,
0.2% by weight of allantoin,
1.0% by weight of tromethamine,
0.2% by weight of perfume,
0.5 percent by weight phenoxyethanol,
Rest of water.

The aforementioned sunscreen can be produced as follows:
The manufacturing process is described for a batch of approx. 100-130 kg of finished product in an ointment machine with a heatable kettle and a paddle stirrer with a scraper and a gap homogenizer.

• 1. The pre-weighed substances of the fat phase are raised together to approx. 80 ° C melted and heated (Cocoglycerides, Oleyl Erucate, Dicaprylyl Ether, Hydrogenated Castor Oil, Cetyl Palmitate, Cyclomethicone, both Dodecyl Glycol Copolymers).
• 2. Benzophenone-3 and isoamyl p-methoxycinnamate are added to the clear melt, short phase homogenization.
• 3. Apply a vacuum to the kettle, activate the stirrer and homogenizer. Suck in the titanium oxide compound powder while stirring / homogenizing at the same time moderate dispersion.
• 4. Establish the water phase in a second boiler. Aqua, glycerol, allantoin, phe nylbenzimidazole Sulfonic Acid, Tromethamine are combined until völ agitated clarity of the solution; may need more tromethamine to neutralize the Sulfonic acid can be added.
• 5. The approx. 75-80 ° C warm water phase is analog 3. in the boiler to the fat phase sucks; Stirrer and homogenizer remain activated at the highest level until the entire Water phase is worked in and then 2 min.
• 6. Active cooling of the batch to room temperature (homogenizer off, only switched on at the highest level if phenoxyethanol and perfume are sucked in at approx. 40 ° C [analogous to 3. via addition funnel]).
  Stirrer at slow speed, same as scraper, during the entire cooling process.
• 7. Filling into tubes, the closure (threaded piece and closure cap) is not sufficient Metal exists because of the pigment content of sanding and abrasion effects Tube metal appear when opening and closing the tube (black abrasion in the ge thread).

In summary, the aforementioned sunscreen has the following properties:

• - Machine capability is guaranteed with the above recipe.
• - A sunscreen manufactured according to the recipe is extremely stable. The galenic stability both with heat (45 ° C over 6 months) and with cold weather load (10 thaw freeze cycles) is caused by the emulsifier complex (dodecylglycol copolymers + glycerol and cetyl palmitate as stabilizers or co-emulsifiers), the solubilization and prevention of recrystallization of benzophenone-3 garan the synergism of cocoglycerides and isoamyl p-methoxycinnamate. The Mikroni sation and ambiphibia effectively prevent pigment sedimentation. The pigmen te or filter substances are practically inactive photocatalytically and to a high degree pho tolysis stable.
• - The sunscreen fulfills the sensory requirements such as pleasant application and easy to remove from the tube, even at low temperatures and on wet Skin without sticking or creating a visible white effect. This will be in the front recipe due to the type of emulsion, the high content of dissolved substances in the water phase and the addition of glycerin. The preparation is therefore in the Can be used universally in both winter and summer.
• - The preparation is due to the type of emulsion and the addition of cyclomethicone (here a short chain) defies a water content of <50% absolutely water and Weld.
• - The recipe comes largely without the known potential allergens and without Petroleum products such as petroleum jelly etc.  
• - The factor combination works perfectly with each other and with the fat phase synergistic, so that UVA and UVB protection with a protection factor of more than 20 is achieved at very low filter substance concentrations.
• - Thanks to its application properties such as high spreading tendency and good distribution, Availability economical in order and therefore very economical.
• - The production proves to be inexpensive, since both are otherwise not unproblematic pigment to be processed matically without producing a predispersion di can be added directly to the batch, on the other hand the water phase by simple Mixture of components can be produced.

The individual components of the aforementioned recipe are defined according to the INCI nomenclature. With regard to the feasibility of the invention, particularly good results are achieved with the following products available on the market in order to produce the aforementioned sunscreen:

• - "MYRITOL 331®" was used as cocoglycerides.
• - "CETIOL J 600®" is suitable as oleyl erucate.
• - "BELSIL CM 040®" is suitable as cyclomethicone:
• - "EUSOLEX T-2000®" was used as the titanium dioxide / alumina / dimethicone blend.
• - As PEG 45- / Dodecyl Glycol Copolymer "ELFACOS ST 9®" is particularly suitable as Methoxy PEG-22 / dodecyl glycol copolymer "ELFACOS E 200®".

Claims (1)

Sunscreen consisting of:
5-10% by weight cocoglycerides,
3-6% by weight isoamyl p-methoxycinnamate,
1-4 weight percent benzophenone-3,
1-4 percent by weight phenylbenzimidazole sulfonic acid,
2-8% by weight micronized, amphiphilic titanium dioxide with low photocatalytic activity
0.5-3 percent by weight tromethamine,
2-5 weight percent PEG 45- / dodecyl glycol copolymer,
2-5 weight percent methoxy PEG 22- / dodecyl glycol copolymer,
4-8% by weight oleyl erucate,
2-8 weight percent dicaprylyl ether,
0.5-5 weight percent cyclomethicone,
Rest of additives and water.