• Applied Chemistry for Engineering
• /
• v.30 no.4
• /
• pp.415-420
• /
• 2019

To investigate the effect of nonionic surfactant and emulsion stabilizer on O/W emulsions, various emulsion formulations with different types of nonionic surfactants and emulsion stabilizers were prepared and their rheological properties were compared. In this study, polysorbate 60 (Tween 60), PEG-60 hydrogenated castor oil (HCO 60), octyldodeceth-16 (OD 16), and ceteareth-6 olivate (Olivem 800) were used as hydrophilic nonionic surfactants, whereas cetyl alcohol, glyceryl monostearate, and stearic acid as emulsion stabilizers. Phase separation occurred only in the emulsion formulation with octyldodeceth-16 and all other emulsion formulations maintained a stable phase. The viscosity, hardness, and creaminess of emulsion formulation using a mixture of ceteareth-6 olivate and cetyl alcohol were the highest, and the emulsified droplet size was also the largest. These results are due to the formation of a network structure texture with the development of a large amount of liquid crystal in the O/W emulsion. In this formulation, the value of elastic modulus was large and the thixotropic behavior, in which the viscosity varies with the history of external force, was observed.

• Journal of the Korean Applied Science and Technology
• /
• v.15 no.2
• /
• pp.25-32
• /
• 1998

The emulsion stability of W/O emulsion prepared by D phase emulsification during storage and handling is studied by using phase diagrams. The process of D phase emulsification begins with the formation of isotropic surfactant solution, followed by formation of oil-in-surfactant (O/D) gel emulsion by dispersion of octamethylcyclotetrasiloxane(OMCS) in the surfactant solution. Polyols were essential components for this purpose. To understand the function of polyols, the solution behavior of nonionic surfactant/oil/water/polyol systems were investigated by the ternary phase diagrams of polyoxyethylene oleyl ether/OMCS/propylene glycol(PG) aqueous solutions. The addition of PG increased the solubility of oil in the isotropic surfactant phase. D phase emulsification method has been applied to a new type of cosmetics. By using this emulsification technique, O/W emulsion were formed without a need for adjust of HLB. Fine and stable W/O emulsions were prepared by D phase emulsion.

• Analytical Science and Technology
• /
• v.21 no.3
• /
• pp.159-166
• /
• 2008

In this study, the characteristics of emulsified fuel and engine emissions were studied. Emulsified fuel which composed of water and diesel was manufactured by using homogenizer and ultrasonic generator. Engine emissions were studied whit engine dinamometer. In emulsified fuel, density and viscosity were increased with increasing water contents, but viscosity was decreased over 60% of water in emulsion fuel. The emulsion type of W/O changed to that of O/W over 60% of water in emulsion fuel. In the results of engine dinamometer test, NOx concentration and smoke density were reduced with increasing water contents in emulsified fuel but reciprocal in the case of THC, CO. Temperature and power were reduced with increasing water contents in emulsion fuel. In conclusion, it seemed that using emulsified fuel for diesel engine was effective for reducing NOx concentration and smoke density.

• Journal of the Korean Applied Science and Technology
• /
• v.37 no.6
• /
• pp.1517-1527
• /
• 2020

This study is about the UV protection effect and water resistance of a multiple emulsion (W/O/W) sunblock cream applied with emotional engineering and reports an actual industrial case. Multiple emulsion system of sunblock cream has the characteristics of changing to a W/O type that is soft and moist when applied, and has excellent water resistance after absorption. Multiple emulsion cream is a highly functional sunblock cream that has both moisture and water resistance. It is a stable milky white cream with a viscosity of 36,000 cps. The organic sunscreen used for the sunscreen was ethylhexylmethoxycinnamate and bisethylhexyloxyphenolmethoxyphenyltriazine. Hexagonal zinc oxide and titanium dioxide that block both UVB and UVA were used. As a result of measuring the UV protection effect by the in-vitro method, the UV protection effect (SPF) is 78.9 for multiple emulsion cream, 76.7 for W/O cream, and 71.3 for O/W cream. It was found that the blocking effect was different. This obtained the highest effect value in the multiple emulsion. As a clinical (in-vivo) result of the UV protection effect, the SPF value representing the UV protection effect of the sunblock cream developed with a multiple emulsion system was 85.7, and the PA-value that blocks the UVA area was 26.5, and ++++. It was found that it has a corresponding high blocking effect. As a result of the water resistance test, the W/O/W formulation had a high waterproofing resistance of 93.8% even after 4 hours, W/O had 75.4%, and O/W had a low water resistance of 25.3%. In the results of the HUT test, it was found in the order of multiple emulsion sun block cream > hydrophilic cream > lipophilic cream. Based on the research results of this multiple emulsion, it is expected to be highly active as a sunblock cream dedicated to outdoor activities by improving the feeling of use, UV protection index, and water resistance. Therefore, in this study, a multiple emulsion system of sunblock cream is developed and has a characteristic that changes to a W/O type that has a soft and moist feeling when applied, and has excellent water resistance after absorption.

• Journal of the Korean Applied Science and Technology
• /
• v.25 no.3
• /
• pp.395-403
• /
• 2008

In this study, the characteristics of emulsified fuel were studied. The emulsified fuel which was composed of water and diesel was manufactured by using homogenizer and ultrasonic generator. The more the percentage of water contents increases, the more the density increases to the emulsified fuel. However, the viscosity increased in the 60% of water contents and decreased in the 70% of water contents because the O/W type was formed. The 3 minutes's ultrasonic waves during the irradiation time was appropriate of 16,000 rpm. And the energy density of ultrasonic waves was 87.5J/g. The emulsion stability has improved in the lower temperature, the lower percentage of water contents, and the most stable emulsion state was obtained from 20%(w/w) of water contents. Also, the emulsion stability was related to the HLB values of emulsifiers. Especially, the HLB values of emulsifier were appropriate from 4 to 7 values.

• Journal of the Korean Applied Science and Technology
• /
• v.29 no.3
• /
• pp.377-392
• /
• 2012

It has been known that small solid particles act as a stabilizer in pickering emulsion system. In this study, we successfully prepared stable pickering emulsion in n-hexylalcohol and water system with $TiO_2$ whose surface was treated by alkylsilane. The optimum condition to prepare pickering emulsion stabilized by $TiO_2$ particles was determined by amount of $TiO_2$ particles and ratio of water and oil phase. The type of pickering emulsion was dependent on wettability of particles for water and n-hexylalcohol. When the amount of $TiO_2$ particles increased up to 5.00 wt%, the stability of pickering emulsion was showed to be improved. The most stable pickering emulsion was prepared in the case of W/O type which has the ratio of oil and water phase (3 : 7). We tried to prepare porous $SiO_2-TiO_2$ composite pigments using a pickering emulsion as template at the optimal condition. Porous pigments were synthesized with Ludox HS-30 as an inorganic material by sol-gel process. The characteristics and shape of porous pigments were measured by optical microscope, SEM, BET, XRD and EDS.

• Proceedings of the SCSK Conference
• /
• 2003.09b
• /
• pp.407-416
• /
• 2003

In this study, we evaluate the correlation between in vitro and in vivo determination of SPF of sunscreen products containing various ingredients depending on emulsification system. For in vitro approach, we determined SPF by the method of Diffey and Robson using an TransporeTM tape(3M Health care, USA) and SPF 290-analyzer(Optometrics Co. USA). SPF values and standard deviations are calculated and displayed after completion of the run. In vivo SPF values are determined according to KFDA (the Korea Food and Drug Administration) method in panels of Fitzpatrick's skin type II or III. We investigated the difference in SPF data of sunscreen ingredient according to emulsification system. The in vivo SPF data is high in water-in oil(W/O) emulsion than in oil-in water(O/W) emulsion samples. The difference may be due to the particular behavior in each vehicles and its presence on skin surface may produce a different sunscreen film. We obtained the corrlation coefficient between in vitro and in vivo SPF data for O/W (R-squre=0.72 )and W/O emulsion(R-squre=0.77). From these results, we suggest the improvement of methodology using Transpore$^{TM}$ tape as substrate to increase the predictability of in vitro method.d.

• Analytical Science and Technology
• /
• v.11 no.2
• /
• pp.79-87
• /
• 1998

Consumers have recently preferred to purchase extensive UV intercepting products, which are waterproof and free from side effects on skin. During the testing of cytotoxicity (in-vitro) in neutral red (NR) method, cell survival ratio of UV-B interceptors decreased to just above 0.08 w/v%, and it was observed that the UV-A interceptors the ratio also decreased to just above 0.06 w/v%. In addition patch-tests of inorganic UV interceptors resulted in no skin irritation even below 10.0 and 11.25. In absorption curves, UV-B was most suitable for octyl methoxycinnamate (OMC) and UV-A for butyl methoxy dibenzoylmethane (BMDM). For this reason, $Nylonpoly^{TM}$ UVA/UVB the material of OMC and BMDM coated with Nylon & polyethylene, was used as the organic UV interceptor. Zinc oxide (ZnO) and titanium dioxide ($TiO_2$) was used as inorganic UV interceptors. The appropriate mixture ratio of ZnO and $TiO_2$ was 6 to 4:6% of ZnO, 4% of $TiO_2$ and 5% of $Nylonpoly^{TM}$ UVA/UVB were all combined and added to our sunscreen cream. The SPF value of in-vitro was 38.9. In practical application, each sun protection factor (SPF) duration of oil-in-water (O/W) emulsion and water-in-silicone (W/S) emulsion containing sunscreen cream of the same content showed that W/S type of sunscreen cream was 5 times as durable as the other. Therefore, this product is fit for use in swimming, climbing or skiing. This research is to minimize skin trouble caused by UV interceptors and to make one with proper softness, skin safety and UV intercepting efficiency.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.30 no.1
• /
• pp.117-122
• /
• 2004

Exessive UV radiation causes a lot of problems in our skin. In order to find out the alternative UV absorber that can safely be used in cosmetics, we have screened various natural extracts in terms of their UV absorbing effect. Some natural extracts, which possess antioxidative activities, have also been found to retard the oxidation process in our experiment. Natural compound such as 7-hydroxycymopol, baicalein, etc. could be transformed into adjuvant UV absorber by chemical modification. In cosmetics, its chemical stability against UV radiation, exposure to oxygen and other factors could be improved by using the silicone or W/S type emulsion. The values of MED (minimal erythema dose) were improved to 0.10 ${\pm}$ 0.02∼0.11 ${\pm}$ 0.02 by adding this natural extract into the cosmetic formulations. In conclusion, the results of the present study show that natural extracts could be used as an adjuvant UV absorber, if they are stabilized.

• Applied Chemistry for Engineering
• /
• v.8 no.5
• /
• pp.763-770
• /
• 1997

The separation of benzene-cyclohexane mixture using (O/W)/O emulsion liquid membrane was studied. The operating parameters which can affect the selectivity, benzene yield, and emulsion size distribution were examined and determined by the batch type operation. The unsteady state and steady state extraction behavior in continuous pulse stirred reactor(CPSR) were verified. The optimum conditions for benzene selectivity and yield in batch operation were as follows; emulsion mixing intensity 4000 rpm, Tween 80 concentration 0.4%, volume ratio of membrane phase to internal phase 0.75, volume ratio of dispersed phase to continuous phase 0.5, and permeation time 10 minutes, As impeller speed increased and the microdrop holdup decreased, the Sauter mean diameter decreased. Turbulence damping parameter of modified Calabrease correlation considering microdrop holdup was 2.28. The optimum conditions of continuous operation were as follows; agitation speed 300 rpm, pulse frequence 2 times/sec, flow rate of continuous phase 30ml/min, and flow rate of emulsion phase 12.0ml/min.