요약목적세미퍼머넌트 아이브로우 제품은 눈썹에 색상이 일시적으로 착색되어 일정기간 동안 메이크업 효과가 지속되는 장점을 지니고 있다. 제품의 지속력에 가장 중요한 요인은 제형과 pH 레벨에 따른다.
방법이 연구에서는 액상형의 세미퍼머넌트 아이브로우 화장품의 pH를 조절하여 Control (pH 6.0), Sample A (pH 5.0), Sample B (pH 4.0), Sample C (pH 3.0)를 제조하였다. 제조된 시료들의 제품 색상을 측정하였으며, 30명의 패널을 모집하여 사용 후 관능평가를 실시하였다.
AbstractPurposeSensory perception and performance are important aspects for the successful development of cosmetic in the market. In this study, we aimed to prepare semi-permanent eyebrow formulations and perform a sensory evaluation of the same.
MethodsWe prepared semi-permanent eyebrow cosmetic (SEC) formulations of different pHs (pH 3.0, 4.0, 5.0 and 6.0) and evaluated the sensory attribute on a 5-point Likert scale. The test panel comprised women aged 20-39 years who were SEC users and were recruited from an organization via invitation.
ResultsIn sensory evaluation, no difference was noted among samples regarding their spreadability and usability. This is attributable to the fact that the tested samples were prepared in the same form as the liquid type of SECs. The SEC (pH 3.0) and SEC (pH 4.0) showed a high satisfaction level for the color strength and tenacity. These results are likely to be related to the pH regulator components (i.e., citric acid and sodium citrate).
IntroductionThe eyebrow cosmetics that had been used are in form of powder, gel, and pencil. Recently, the use of semi-permanent eyebrow cosmetic had been trending worldwide and had been shown to have great advantage (Hong, 2018) in keeping the color on the eyebrows for a certain time period. The long-lasting effect of semi-permanent cosmetics mainly depends on the pH level and properties of the pigments.
The surrounding pH increases in an area where the pH is always around 6 due to human homeostasis (Lambers et al., 2006); this leads to the release of the cosmetic ingredients from the particles and their absorption through the skin (Lee & Kim, 2011; Zografi, 1985). Li et al. (2012) reported that the penetration and absorption of azelaic acid had a strong pH- and vehicle-dependency. In addition, pH values between 4.0 and 5.0 appeared to provide the most favorable environment for passive diffusion since the concentration of unionized methotrexate would be optimal in this range (Vaidyanathan et al., 1985).
This study was based on the importance of the pH effect on percutaneous absorption, although the material and formulation used were different. We prepared semi-permanent eyebrow cosmetic formulations at various pH levels of 3.0, 4.0, 5.0, and 6.0.
Market success is governed by fulfilling research expectations, and by the customer identified sensory attributes that dominate. This implied that sensory analysis significantly contributed to the characterization of individual products (Moravkova & Filip, 2016). The advantage of sensory evaluation is that the quality of the products is perceived by the end users. The objective of this study is was sensory evaluation of semi-permanent eyebrow cosmetic formulations at various pH levels, with emphasis of characterization of semi-permanent eyebrow cosmetics.
Methods1. Materials and preparationThe ingredients of the cosmetics included solvents, thickeners, sequestering agents, preservatives, pigments, and pH regulators. The pH regulators were obtained as a sodium acid from Duksan Pure Chemicals Co., Ltd. (Ansan, Korea) and as citric acid from RZBC Co., Ltd. (Shandong, China). The pigments and ingredients were purchased from Sigma-Aldrich (USA). The composition of the semi-permanent eyebrow cosmetics is shown in Table 1.
Phase A was prepared by dissolving 1 g butylene glycol, 3 g glycerin, 0.2 g Coceth-7, 0.2 g PPG-1-PEG-9 lauryl glycol ether, 0.4 g emulgin, 0.05 g disodium EDTA, 0.2 g methylparaben, and 0.1 g propylparaben in 53.17 g of distilled water. Phase B consisted of 0.33 g orange #205, 0.3 g black #401, and 0.05 g red #106 dissolved in 20 g distilled water. Phase C was prepared by mixing 6 g benzyl alcohol, and 9 g ethanol. Phase D consisted of citric acid and sodium citrate, which were the pH regulators. The amount of pH regulator was different for each sample. A, B, C and D phases were mixing to manufacture the semi-permanent eyebrow cosmetics. Thereafter, the pH regulators were added to the semi-permanent eyebrow cosmetics and mixed using the homomixer. The prepared A, B, C and D phases were mixed, defoamed and filtered, and stored in a cold sealed state. The preparation process of semi-permanent eyebrow cosmetic is showen in Figure 1. The prepared semi-permanent eyebrow cosmetics conformed the fundamentals of stability test (Cannell, 1985).
2. Panel recruitingThe panels comprised 30 women in the organization who were aged between 20-39 years and who were semi-permanent eyebrow cosmetic users. Informed consent was obtained from the subjects after providing them with written and oral information about this study. The study protocol was approved by the ethics committee of Wonkwang University (Registration No. WKIRB 201706-038-02). The panels were blinded to the information on the sample's pH level and used the prepared semi-permanent eyebrow cosmetics (i.e., control, SEC (pH 5.0), SEC (pH 4.0) and SEC (pH 3.0)). The subjects were asked to evaluate the sensory attributes of spreadability, color strength, tenacity, usability by the 5-Likert scale.
3. Color measurement of semi-permanent eyebrow cosmeticThe 25 μL of semi-permanent eyebrow cosmetics was applied on the opacity chart, and the samples were allowed to dry at room temperature for 30 min. The film thickness of the semi-permanent eyebrow cosmetics was 10 μm in each sample. The samples' colorant was determined using a spectrum colorimeter with Φ an 8 mm aperture size (CM-700d Spectrophotometer Minolta, Tokyo, Japan). The color value was measured as the CIE color system (L*, a*, and b*). The value for the whiteness index was displayed only when the observer 10° and the illuminant D 65 were selected.
4. Sensory analysisThe panel was requested to score each of the four semi-permanent eyebrow cosmetics after seven days of actual use. Four sensory attributes were chosen and included spreadability on the eyebrow, color strength after cleansing, tenacity on the skin, and usability (Table 2). The scales ranged from 1 (very dissatisfied) to 5 (very satisfied) using a 5-Likert scale.
5. Statistical analysisAll the statistical analyses were conducted using SPSS ver. 24.0 software (SPSS Inc., USA). The data were presented as mean and standard deviation. The results were subjected to one-way analysis of variance, and significant differences were determined by the Duncan's multiple range test at p<0.05.
Results and DiscussionFrom the values of the lightness (L*), yellowness (a*), and redness (b*) components, we can obtain a better understanding of the characteristics of the total color difference among the samples (Melgosa et al., 2018). The color values of the semi-permanent eyebrow cosmetics based on the spectrum colorimeter are shown in Table 3. The mean value of control color values was L*=31.29, a*=-0.4, b*=-0.23, which indicated dark gray without yellowness and redness. The color values of the SEC (pH 5.0), SEC (pH 4.0), and SEC (pH 3.0) were in the same series of dark brown. Notably, all samples from the semi-permanent eyebrow cosmetics, comprised equivalent amount of the pigment ingredients, although there was a difference between among the color values of samples. There was a tendency of having more reddish and yellowish coloration in the samples that contained pH regulators. One interesting finding was that the pH regulator affected the colorant of the semi-permanent eyebrow cosmetics. In accordance with the present result, Seo et al. (2017) reported that anthocyanin pigments were especially sensitive to pH and the redness (a*) increased in acid.
The results of the sensory analysis are numerically summarized in Table 4 and graphically depicted in Figure 2. The spreadability and usability were not significantly difference among the groups. The cosmetics may have contained the controlling factor in the release of the active ingredient from the formulation. This result can be explained by the fact that the tested samples were prepared in the same form as the liquid type of semi-permanent eyebrow cosmetics.
In terms of color strength, satisfaction was higher for the SEC (pH 5.0), SEC (pH 4.0) and SEC (pH 3.0) than for the control. Furthermore, SEC (pH 4.0) and SEC (pH 3.0) had the highest satisfaction for tenacity among the tested samples. These results were likely to be related with the pH regulator contained in the samples. Most cosmetics or pharmaceuticals are formulated at pH values at least below 5.0, based on the understanding that such pH is beneficial for the human skin. Acidic formulations are well known to be more effective at a lower pH because of the increased skin penetration of the active ingredient (Blaak et al., 2017; Wiechers et al., 2006). The pH range of cosmetics regulated by the Korea Food and Drug Administration (KFDA) is pH 3.0 to 9.0. However, Song et al. (2018) reported that 3.3% developed skin irritation on human repeat insult patch test after 48 hours of exposure to a semi-permanent eyebrow cosmetic at pH 3.0. Cosmetic are products used over long periods by the public and their safety is very important (Alani et al., 2013; An et al., 2014; Aschenbeck et al., 2017). The result of that previous study indicated than the acidic pH 3.0 of semi-permanent eyebrow cosmetics may have caused the doubtful reaction with continuous use, although an acidic pH 3.0 cosmetic is available and is regulated by the KFDA.
ConclusionSensory analysis of the use of semi-permanent eyebrow cosmetics showed a significantly high satisfaction with color strength and tenacity at a lower pH level. The formulation with a lower pH level (below 4.0) was beneficial for maintaining the coloration (color strength and tenacity) of the semi-permanent eyebrow cosmetic.
AcknowledgementsThis work was supported by the National Research Foundation of Korea Grant funded by the Korean Government (NRF-2017S1A5B5A02025240).
Figure 2.Graphic evaluation of the sensory attributes.Graphic organize is a visual display that demonstrates relationships between sensory attributes. Data are show as mean (N=30). Control, pH 6.0, did not contain the pH regulator; SEC (pH 5.0), semi-permanent eyebrow containing 0.145 g citric acid and 0.25 g sodium citrate; SEC (pH 4.0), semi-permanent eyebrow containing 0.5 g citric acid and 2.05 g sodium citrate; SEC (pH 3.0), semi-permanent eyebrow cosmetic, containing 0.5 g citric acid and 0.1 g sodium citrate.
![]() Table 1.Formulation of semi-permanent eyebrow cosmetics (Unit: g) Table 2.Sensory attributes of semi-permanent eyebrow cosmetics Table 3.The colorant of semi-permanent eyebrow cosmetics
Table 4.The results of sensory evaluation in semi-permanent eyebrow cosmetic Measurement data were done in triplicate. Data are show mean±standard deviation. The one-way ANOVA was used to compare the control, SEC (pH 5.0), SEC (pH 4.0), and SEC (pH 3.0). Statistical significance was found at **p <0.01, ***p <0.001. a, b, c, Duncan's post-analysis result between characters. Within the same row, value with the same letters are not significantly different. ReferencesAlani JI, Davis MD, Yiannias JA. Allergy to cosmetics: a literature review. Dermatitis 24: 283-290. 2013.
![]() ![]() An SM, Ham H, Choi EJ, Shin MK, An SS, Kim HO, Koh JS. Primary irritation index and safety zone of cosmetics: retrospective analysis of skin patch tests in 7440 Korean women during 12 years. International Journal of Cosmetology Science 36: 62-67. 2014.
![]() Aschenbeck KA, Warshaw EM. Allergenic ingredients in personal hygiene wet wipes. Dermatitis 28: 317-322. 2017.
![]() ![]() Blaak J, Dähnhardt D, Dähnhart-pfeiffer S, Bielfeldt S, Wilhelm KP, Wolfart R, Staib P. A plant oil-containing pH 4 emulsion improves epidermal barrier structure and enhances ceramide levels in aged skin. International Journal of Cosmetic Science 39: 284-291. 2017.
![]() ![]() Cannell JS. Fundamentals of stability testing. International Journal of Cosmetic Science 7: 291-303. 1985.
![]() ![]() Hong SN. Effect of preference for semi-permanent makeup on procedure satisfaction. Asian Journal of Beauty and Cosmetology 16: 165-177. 2018.
![]() ![]() Lambers H, Piessens S, Bloem A, Pronk H, Finkel P. Natural skin surface pH is on average below 5, which is beneficial for its resident flora. International Journal of Cosmetic Science 28: 359-370. 2006.
![]() ![]() Lee E, Kim B. Smart delivery system for cosmetic ingredients using pH-sensitive polymer hydrogel particles. Korean Journal of Chemical Engineering 28: 1347-1350. 2011.
![]() ![]() Li N, Wu X, Jia W, Zhang MC, Tan F, Zhang J. Effect of ionization and vehicle on skin absorption and penetration of azelaic acid. Drug Development and Industrial Pharmacy 38: 985-994. 2012.
![]() ![]() Melgosa M, Richard N, Fernández-Maloigne C, Xiao K, de Clermont-Gallerande H, Jost-Boissard S, Okajima K. Colour differences in Caucasian and oriental women's faces illuminated by white light-emitting diode sources. International Journal of Cosmetic Science 40: 244-255. 2018.
![]() Moravkova T, Filip P. Relation between sensory analysis and rheology of body lotions. International Journal of Cosmetic Science 38: 558-566. 2016.
![]() ![]() Seo ES, Park CH. Hair dyeing and colorfastness using extracts of blueberry. Asian Journal of Beauty and Cosmetology 15: 323-332. 2017.
![]() ![]() Song SM, Yu SJ, Kim JH. The cell viability & patch test of semi-permanent eyebrow cosmetic depending on various pH Levels. Journal of the Korean Society of Cosmetology 24: 977-985. 2018.
Vaidyanathan R, Chaubal MG, Vasavada RC. Effect of pH and solubility on in vitro skin penetration of methotrexate from a 50% v/v propylene glycol-water vehicle. International Journal of Pharmaceutics 25: 85-93. 1985.
![]() Wiechers JW, Kelley CL, Blease TG, Dederen JC. Formulating for fast efficacy. Journal of Cosmetic Science 57: 191-192. 2006.
![]() Zografi G. Physical stability assessment of emulsions and related disperse systems: a critical review. Journal of Society Cosmetic Chemists 33: 345-358. 1985.
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