Development, physicochemical and functional analysis of anti-frizz leave-on emulsion with coconut oil

Abstract

Introduction: The cosmetics industry increasingly offers a greater variety of products to consumers, as people have a constant need to change their appearance. For the past years, women have followed a tendency to have their hair back to its natural color, since it was altered by chemical straightening for a long time. The purpose of this paper was to produce and assess the physicochemical stability of a leave-on emulsion formulation containing coconut oil for anti-frizz action. Methods: It was developed a cationic emulsion formulation, with coconut oil as the active agent in 0.5% and 1.0% concentrations. It was performed functional tests in damaged hair strands. A preliminary stability test was conducted, and the samples were packaged in polyethylene containers, and subjected to different conditions (temperatures of 5°C, 25 °C and 45°C and direct exposure to sunlight). They were analyzed on day 0 and on day 15. The physicochemical analyses were: organoleptic characteristics (color, odor and appearance), pH, spreadability, apparent density and centrifugation. The functional tests (combability test and test on strands of hair) were conducted in strands of damaged hair. For the combability test, which measures the easiness of combing, the strands were previously washed with neutral shampoo. The samples, after being applied, were manipulated for 1 minute in the strands. After the application, a fine-tooth comb was slid through the hair length for at least 5 times. Then we measured the slid length. For the test on strands, they were placed in room temperature (23ºC) and relative humidity (33%) for 24 hours. After such period, we considered half the length of strands for width. After spreading, we examined the anti-frizz action. The results were photographed. The statistical test t was applied: sample data, with the BioEstat 5.3 program. Results: We found that the color and odor were slightly altered only in samples exposed to sunlight. As for appearance and centrifugation, the samples remained homogeneous under all conditions. The pH of the samples ranged 4.0 – 4.6. In the spreadability test, we found variations of 7.93 –14.72. In the combability test, there was no significant difference in slid between the formulation with coconut oil 0.5% and the formulation with coconut oil 1.0%. Nevertheless, there was difference when they were compared to the sample without the active agent. Conclusion: In the test on strands of hair, the sample with 1.0% of the active agent (coconut oil) had the best volume result.