50000 45000 40000 35000 30000 ,s en 25000 20000 15000 10000 5000 0 0 VITAMIN A PALMITATE PHOTOSTABILITY 5 10 15 20 shear rate (s- 1 ) 25 30 245 -+-2s•c liposomes 1d u. --o-2s·c liposomes 1d e. ......,_2s•c liposomes 30d U. --6-2s·c liposomes 30d B. -x-2s·c TagraA11du. -25"C Tagra A1 1d B. ----- 25"C TagraA1 30d U. --2s·c Tagra A1 30d B. -25"C BHT 1d U. ---25'C BHT 1d B . _.,_25"C BHT 30d U . --0-25"C BHT 30d B. ......,_25"C alone 1d U. 25"C alone 1d B. -+-25"C alone 30d U. --0--25°C alone 30d B. Figure 8. Flux rheograms of the gels at pH 5.6, containing retinyl palmitate alone and with BHT®, Tagravit® A1 miccocapsules, and Lipotec® liposomes, after one and 30 days at 25°C. 30000 25000 m 20000 rn 15000 rn 10000 rn 5000 0 0 5 15 20 25 -+-40°C liposomes 1d U. --0--40°C liposomes 1d B. ---r-40°C liposomes 30d U. ---6-40"C iposomes 30d B. �-40•c TagraA11d u. ---«-40"C Tagra A1 1d B . ·---40°C TagraA1 30d U. --4o•c TagraA1 30d B. -40°C BHT 1d u. -0-40°C BHT 1d B. -40"C BHT 30d U. �40°C BHT 30d B. ---6-40°C alone 1 d U _ --6-40°C alone 1d B. -+-40°C alone 30d U. 30 --0-40°C alone 30d B. Figure 9. Flux rheograms of the gels at pH 5.6, containing retinyl palmitate alone and with BHT®, Tagravic® A 1 miccocapsules, and Lipocec® liposomes, after one and 30 days at 40°C.

246 JOURNAL OF COSMETIC SCIENCE 25000 -+-2s•c nposomes 1d U. 20000 --o-2s·c fiposomes 1d e. -&--2s•c liposomes 30d u. ---.!r-2s·c liposomes 30d B. 15000 -x-2s·c TagraA1 1d u. "' -::r.:-2s·c TagraA11d B. -------25'C Tagra A1 30d U. --2s·c Tagra A 1 30d e. 10000 -25°C BHT 1d u. "' --0-25'C BHT 1d B. --25°C BHT 30d U. 5000 --0-25°C BHT 30d B. ---A--25°C alone 1d u. -tlr-25°Calone 1d e. --+-2s·c ai1one 30d u. 0 2s·c alone 30d e. 0 5 15 20 25 30 Figure 10. Flux rheograms of the gels at pH 7.0, containing retinyl palmitate alone and with BHT®, Tagravit® A 1 microcapsules, and Lipotec® liposomes, after one and 30 days at 25 ° C. 15000 rn 10000 '- '- rn 5000 0 5 15 20 shear rate (s- 1 ) 25 30 --+-40°cliposomes 1d u. --0--40°Cliposomes1d B. -&--40°CHposomes 30d U. -6-40"C llposomes 30d B. -X-40'C TagraA11d U. -ll:-40°CTagraA11d B. -- 40°C Tagra A1 30d U. --40•c Tagra A1 30d B. -40•c BHT 1d U. -0-40°C BHT 1d B. -40•c BHT 30d U. -0-40°C BHT 30d B. ___....,..40°Calone1d U. ---il-40'C alone 1d B. -+-40°Calone30d U. 40°Calone30d B. Figure 11. Flux rheograms of the gels at pH 7.0, containing retinyl palmitate alone and with BHT®, Tagravit® A 1 microcapsules, and Lipotec® liposomes, after one and 30 days at 40°C.