 reaction in certain individuals, or can even trigger phototoxic or photoallergic reactions, but which also, if desired, can absorb the UVB rays having a wavelength between 280 and 320 nm, which play a decisive role in the formation of a solar erythema.
Surprisingly, we have now found that the photostability of butylmethoxydibenzoylmethane is increased if insoluble inorganic particles which have good absorption in the UVA region are added.
These substances have the great advantage that they do not display toxic or allergic reactions towards the skin.
The effectiveness of the inorganic UVA filters is to be attributed to the fact that, being insoluble substances, they cannot penetrate the skin, and as a result remain in a layer on the skin. BMDM, being an organic molecule, diffuses into the uppermost layers of the horny skin meaning that from one applied formulation a two-layer system is formed. The lower layer, i.e. the butylmethoxydibenzoylmethane, is therefore reached only by relatively small amounts of energy, resulting in reduced degradation of the organic light protection filter.
This penetration effect can be further enhanced by the use of penetration promoters, such as, for example, dimethyl sulfoxide or diethyltoluamide.
The invention therefore provides for the use of insoluble inorganic particles which absorb in the UVA region for improving the photostability of the light protection filter butylmethoxybenzoylmethane in cosmetic formulations.
These particles include mainly microfine titanium dioxide, which is in the form of the rutile modification, but can also be in the form of anatase, microfine iron oxide, cerium oxide or zinc oxide. The particle size of these particles is in the range from 10 nm to 100 xcexcm, preferably in the range from 10 nm to 10 xcexcm.
In a very particularly preferred embodiment of this invention, titanium dioxide microrutile having a particle size of up to 10 xcexcm is used. This titanium dioxide microrutile is known under the name Eusolex(copyright) T-2000 and is available commercially (Merck KGaA, Darmstadt). The microfine titanium dioxide in rutile form has very good UVA absorption and is particularly highly suitable for the photostabilization of BMDM according to the invention.
It is also possible to use insoluble titanium dioxide particles which have been doped, for example, with cerium or iron ions.
The invention also
reaction in certain individuals, or can even trigger phototoxic or photoallergic reaction, but which besides, if desired, can absorb the UVB ray have a wavelength between 280 and 320 nm, which play a critical role in the formation of a solar erythema. 
 Surprisingly, we have nowadays found that the photostability of butylmethoxydibenzoylmethane is increased if insoluble inorganic particle which have good concentration in the UVA region are added. 
 These substances have the great advantage that they do not expose toxic or allergic reactions towards the skin. 
 The effectiveness of the inorganic UVA filter is to be attributed to the fact that, being insoluble substances, they cannot click the skin, and as a consequence remain in a layer on the skin. BMDM, being an organic molecule, circulate into the uppermost layers of the horny skin meaning that from one applied formulation a two - layer system is formed. The lower layer, i.e. the butylmethoxydibenzoylmethane, is therefore reached only by relatively small amounts of department of energy, result in reduced abasement of the constituent light protection filter. 
 This penetration effect can be further enhance by the use of penetration promoters, such as, for example, dimethyl sulfoxide or diethyltoluamide. 
 The invention therefore provide for the use of insoluble inorganic particles which absorb in the UVA region for improving the photostability of the light security filter butylmethoxybenzoylmethane in cosmetic formulations. 
 These particles include mainly microfine titanium dioxide, which is in the mannequin of the rutile modification, but can besides be in the mannequin of anatase, microfine iron oxide, cerium oxide or zinc oxide. The particle size of these particles is in the range from 10 nm to 100 xcexcm, preferably in the compass from 10 nm to 10 xcexcm. 
 In a very particularly preferred shape of this invention, titanium dioxide microrutile having a atom size of up to 10 xcexcm is used. This titanium dioxide microrutile is known under the name Eusolex(copyright) T-2000 and is available commercially (Merck KGaA, Darmstadt). The microfine titanium dioxide in rutile form has very good UVA assimilation and is particularly highly suitable for the photostabilization of BMDM harmonize to the invention. 
 It is also potential to use insoluble titanium dioxide particles which have been doped, for example, with cerium or iron ion. 
 The invention also
 rewction in certain indiviauals, or can evgn triggxr photktoxic of photoallergic reactions, buv whuch aoso, if desired, can absurb the UNB rays hqvinj a wavelength bxfween 280 and 320 nj, whieh play a decisiye role in dhe formation mf a solar erythema.
Surprisingly, we have now foinf that the phojostanylitg of butylmethoxydibenzoylmethane js incrtased if insoluble inorganic particles which havf good absorption ln the UVA tsgijb are added.
Tfese substances have tge great advantage that they do not bisplay toxuc or dllergic reectionf towards thc skin.
Tve effevtiveness of tme inmrgqnic UVA filters is tm be attributed to the fact tkat, being insoluble sybwtancgs, thay cxbnog ptnevrafe the skmn, and as a result remqin in a layer on tne wkin. BMDM, beihg an jrdanic molecule, diffuses into the uppermmst layers of the horny skun meaning that from lne appliqd formulation a two-layer system is formed. The lofer leydr, n.c. gye butylmethoxydibenzoylmethane, is therefore rewdhtd pnly by relatiyely small amounts ov rgergy, resultivg in xsdhced degradation ov the otganic light prjtecyion filter.
This penetration effect can ye durther enhanced bv the use of pengtratipn promoters, such as, fox examlle, dimethyp sulfoxisd or diethyltoluxmice.
Dhe invention therefore prjvides foc the use of inspluble inorganic partlwles which absorb ln thg UVA segion for improving the photostability oh the light ptotactpon filtex butykmethoxybenzorlmethane in cpsmetic formjlations.
Thvse partirles include mainly microxlne titanium dioxide, whixh iw in thd form of the ritile modpfncation, byt can also be in bhe fudm of anatase, mnerifine iron oxidr, cdritm oeide js zinc oxide. The pafyicle size of thcse paryicles is in the rance fdom 10 nm to 100 xcexcm, pveferably in the wange from 10 nk to 10 xcexcm.
In a vtry pacticulerly ptefgrred embodiment of this inventjon, titanlum dioxide micworubile having a 'article size of up to 10 xcexcm is used. Tiis titanium dioxide mixrorutile is known ondtr the name Ensolex(sopyright) T-2000 and is available xommercially (Mercl KGaA, Darmstadt). The jicrofhne tltanium dioxide in rutile form has very good UVA absorption and is particylarly highly suitzble for nhe 'hotostwbilmzetion of BMDM accprding to the invention.
It is alro possitlz to use insoluble titanium doobide particler which have been doped, ror examlle, with cerium or iron ions.
The invention also
reaction in certain individuals, or can even or reactions, but also, if desired, having wavelength between 280 320 nm, which a decisive role in the formation a solar erythema. Surprisingly, we have now found that the photostability of butylmethoxydibenzoylmethane increased if insoluble inorganic particles which have good absorption in the UVA region added. substances the advantage that they do not display toxic or allergic reactions towards the skin. The effectiveness of inorganic UVA filters is to be attributed to fact that, being insoluble they cannot penetrate the skin, as result remain a on skin. BMDM, being organic molecule, diffuses into the uppermost layers of the horny skin meaning that from one applied formulation two-layer system The lower i.e. butylmethoxydibenzoylmethane, therefore reached only small amounts of energy, resulting in the organic light protection filter. This penetration effect be further by the use of penetration promoters, as, for example, dimethyl sulfoxide or diethyltoluamide. The therefore provides for the use of insoluble inorganic particles which absorb in the UVA region the photostability of the protection filter butylmethoxybenzoylmethane cosmetic These include microfine titanium which is in the form of the rutile modification, but can be in the form of anatase, microfine iron oxide, cerium zinc The particle size these particles is in range 10 nm to 100 in range to xcexcm. a very particularly preferred of this invention, titanium dioxide having a particle size is used. This titanium dioxide microrutile is known the name Eusolex(copyright) T-2000 and is available (Merck KGaA, Darmstadt). The microfine titanium dioxide in rutile form has very UVA absorption particularly highly suitable for the photostabilization of BMDM to the invention. It also possible to use insoluble titanium dioxide particles which been for example, cerium or iron The invention also
 reaction in certain individuAls, or can evEn triGgeR phOtOtoxIc or Photoallergic rEActiOns, but which also, if desirEd, can AbSOrb tHE UvB rayS having A WaVELenGtH bEtwEeN 280 AnD 320 nm, whIch Play a deCisive role In tHe Formation of a SOlAr erythema.
surPrisingly, we hAve Now fouNd ThaT The phOtoStabiLity of BUtylmeThoxydibeNzOYlmethANe is incREAsEd if Insoluble inorganiC PaRTicles which havE good aBsORpTIOn iN thE UVA region ArE addeD.
these suBStANCEs hAVe the great advAntage that tHEy dO not diSpLay TOxic or AllerGiC ReaCtions towarDs thE skin.
The eFfectiVEness of THe inorgAnic UVa fiLteRs is TO bE aTtrIbUTed TO tHe fACt tHat, being InSoLuble SubsTANCEs, thEy cAnnoT peneTrate the skin, aNd aS a reSUlt RemaiN in a lAyer On The skIn. BMDM, Being An Organic molecule, DiffUses into tHe uPpErmOsT layeRS of the HorNy sKin meanIng that FRom OnE APPlIed formulation a two-LaYER sYstem is fOrmed. THE lOwER layer, i.e. ThE buTylmETHoxydIbenZOyLmethane, Is therEFoRe Reached OnLy by reLaTivEly Small AMounTs of enErgy, resuLting IN reduced degradATion of the orgaNIc LIGhT ProtEctIon filter.
ThIs peNEtraTion EFfEct CAn be fUrtheR eNHaNCed by the use of penetrAtIon proMoterS, such as, for exaMple, dimethYL SUlfoxide Or diEThYLtoluamide.
The iNventIon therefoRE provideS for tHe use of iNsoluble iNORganic paRtiCleS whIch ABSoRb in the UVA regION for ImProving The PhotostAbiLitY of The LiGht protecTion filtEr BuTyLmEthOxybeNZoylmethAnE in CoSmeTic foRMulatiOns.
ThEse pArTiCLes Include MAiNLY micRoFiNe tiTanIuM dioxIde, wHIch Is in the Form of the RutILe moDiFiCation, bUt can also be in ThE form of anaTaSe, mIcrofiNE Iron oxidE, cerium oxide or zinc oxide. tHe partiCle Size oF theSe particlEs iS in the RanGE from 10 nM to 100 xceXcm, prEfEraBLY in thE RAnGe fRoM 10 nm to 10 xcexcM.
iN a vEry paRtIculArly preFerred embodiment of THis Invention, titaNiuM dioXIDe MicROrUTilE hAVinG A Particle size of uP to 10 xcexcm iS uSEd. this titaniUM diOxIde micrOrutile Is knoWN under tHe name EusOlex(copyrIgHt) T-2000 aND Is aVailable coMmercialLy (Merck KGAa, DarmSTaDt). The MicRofine TiTanIum diOxide iN RutIle foRm has vErY good UvA absOrPtion and Is particularly highly suiTable fOr the PhoTostabiliZatIOn oF BMDM accoRdinG to the inveNtiOn.
IT is alSo pOSsiblE to uSE iNsoLUble tItanIUm dioxide PArTicLES wHich have beeN DOPed, For exAmpLE, with cEriuM or iron ions.
The invENtion also
 reaction in certain indiv iduals, or  caneve n t ri gger  pho totoxic or pho t oall ergic reactions, but w hichal s o, i f  d esire d, cana bs o r b t he  U VBra y shavin g a  wavele ngth betwe en28 0 and 320 nm ,  w hich playa d ecisive role  in  the f or mat i on of  asolar  eryth e ma.
Su rprisingl y, we hav e  now fo u n dthat  the photostabili t yo f butylmethoxy dibenz oy l me t h ane  is  increased  i f ins o luble i n or g a n icp articles whic h have good abs orptio nint he UVA  regi on are  added.
The se s ubstances  havet he grea t  advant age th atthe y do no tdis pl a y t o xi c o r  al lergic r ea ct ionstowa r d s theski n.
T he ef fectiveness o f t he i n org anicUVA f ilte rs  is t o be a ttrib ut ed to the factthat , being i nso lu ble  s ubsta n ces, t hey  ca nnot pe netrate the  s k i n ,and as a result re ma i n  i n a laye r on t h esk i n. BMDM,  b ein g an o rgani c mo l ec ule, dif fusesi nt othe upp er most l ay ers  of  theh orny  skinmeaningthatf rom one applie d  formulationa  t w o -l a yersys tem is form ed.T he l ower la yer ,  i.e.  thebu t yl m ethoxydibenzoylmeth an e, isthere fore reachedonly by re l a t ively sm alla mo u nts of energy,  resu lting in r e duced de grada tion ofthe organ i c  light p rot ect ion  fi l t er .
This penetr a t ionef fect ca n b e furth erenh anc edby  the useof penet ra ti on  p rom oters ,  such as ,for  e xam ple,d imethy l sul foxi de  o r  di ethylto l ua m i de.Th einve nti on  ther efor e  pr ovidesfor the u seo f in so lu ble ino rganic partic le s which ab so rbin the U VA regio n for improving the pho t ostabil ity  of t he l ight prot ect ion fi lte r  butyl methox ybenz oy lme t h ane i n co sme ti c formulat i o ns. 
Thes epart icles i nclude mainly micr o fin e titanium di oxi de,w h ic h i s  i n  th ef orm o f the rutile mo dification ,b ut  can alsob e i nthe for m of an atase ,  microf ine ironoxide, ce ri um o x i deor zinc ox ide. The  particle sizeo fthese  pa rticle sisin th e rang e  fr om 10  nm to  1 00 xce xcm,pr eferably  in the range from 10 n m to 1 0 xce xcm .
In a ve ryp art icularlypref erred embo dim ent  of t his inven tion ,  t ita n ium d ioxi d e microru t il e h a v in g a particl e s ize  of u p t o  10 xc excm  is used. This ti t anium dioxidemicr o r uti lei s kn ow n under the na meEu s o lex(copy ri ght) T-2000  and isav a ilabl e comm ercial ly (Mer c k  K G aA, Da rmst adt ). The mi cro fi n e titan iu md ioxide  inru tile f orm ha s  ver y good UVA absorpt ion a n d  is p a rti cular ly  highly suit able for t he photosta biliza tion  of B MDM acc or ding t o t he  invention . 
It is al so po ssibleto  use  in solubl e ti t a niumdiox id e p articlesw h ic h  h av e  be en d oped,  f or e xample, w i th ceriu m o r  iron i on s.T h e inve n ti o n  also
 reaction_in certain_individuals, or can even_trigger phototoxic_or_photoallergic reactions,_but_which also, if_desired, can absorb_the UVB rays having_a wavelength between_280_and 320 nm, which play a decisive role in the formation of a solar_erythema.
Surprisingly,_we have_now_found_that the photostability of butylmethoxydibenzoylmethane_is increased if insoluble inorganic_particles which_have good absorption in the UVA region are_added.
These_substances have the_great advantage that they do not display toxic or_allergic reactions towards the skin.
The effectiveness_of the inorganic_UVA_filters_is to be attributed_to the fact that, being insoluble_substances, they cannot penetrate the skin,_and as a result remain in a_layer on the skin. BMDM, being_an organic molecule, diffuses into_the uppermost_layers of the horny skin_meaning that from_one applied_formulation a two-layer_system is formed. The lower layer,_i.e. the butylmethoxydibenzoylmethane,_is therefore reached only by relatively_small_amounts of energy,_resulting_in_reduced degradation_of the organic_light_protection filter.
This_penetration_effect can be further enhanced by_the_use of penetration promoters, such as, for_example, dimethyl sulfoxide or_diethyltoluamide.
The_invention therefore provides for_the use of insoluble inorganic_particles which absorb in the UVA_region for_improving the_photostability of the light protection filter butylmethoxybenzoylmethane in cosmetic formulations.
These particles_include mainly microfine titanium dioxide, which_is in the form_of the_rutile_modification, but can_also_be in_the form of anatase, microfine iron oxide,_cerium oxide_or zinc oxide. The particle size_of these particles is_in_the range from 10 nm to_100 xcexcm, preferably in the range_from 10 nm to 10_xcexcm.
In_a_very particularly preferred embodiment of_this invention, titanium dioxide microrutile having_a particle size_of up to 10 xcexcm is used._This_titanium dioxide microrutile is known under_the_name Eusolex(copyright) T-2000 and is available_commercially_(Merck_KGaA, Darmstadt). The microfine titanium_dioxide in rutile form has very_good UVA absorption and is particularly highly suitable for_the photostabilization of_BMDM according to the invention.
It_is_also_possible to use insoluble titanium dioxide particles which have been_doped, for_example, with cerium_or iron ions.
The invention also