Aqua Keep 10SH-NFC - koboproductsinc.com

1 Contact Chemicals : Lorna RadfordTechnical DevelopmentChemistIntroductionAqua keep 10SH-NFC is an aqueous thickener with an interestingrheology. It forms hazy gels that are structured in bulk but theviscosity breaks on the skin to give a water thin viscosity of aqua keep depends on percentage of aqua keep andpH according to the graph below which are in Kobo s brochure:Figure 1- viscosity versus amount of aqua keep 10SH-NFC used in water,from Kobo s brochureFigure 2- viscosity of a mixture of aqua keep 10SH-NFC in waterversus pH, from Kobo s brochureKobo Products, So. Clinton Plainfield, NJ 07080 USAtel +1 (908) 757-0033fax +1 (908) 757-0905 Kobo Products, SAS135 Rue BuissonniereQuartier Bouysset31670 LABEGEF rancetel +33 (0)5-62-88-77-40fax +33 (0)5-62-88-77-49 Kobo Brasil Bambor - S o Paulo/SP04278-060 Brasiltel +55 (11) 5062-0634 Kobo Dispatek Nihombashi-bakurochoChuoku, Tokyo, 103-0002 Japantel +81 (3) , 2015 aqua keep 10sh -NFCHow to Use GuideAqua keep 3-Adding the powder all at once and then stirring with a spatula leads to lumps of drypowder caught in the gel.

2 Waiting 5-10 minutes allows hydration of these clumps to form ahomogeneous aqua keep in water does not form a gel-this can be seen by the smooth surface (left) after stirring. aqua keep in water does form a gel as shown by the uneven surfaceafter to AddAqua keep 10SH-NFC can be added directly to cold water. Upon addition, it immediately starts toswell and thicken the with a spatula and waiting for several minutes leads to a homogeneous gel; however, it ispreferable to sprinkle over water while paddle stirring. This is because addition without stirringcan lead to formation of clumps which wet at the surface and then the middle of the clumpremains dry. These will eventually hydrate and swell, wait for 10 minutes. How Much to aqua keep in water does not form a gel, it just thickens the water very slightly; keep in water forms a thick gel in bulk. The more aqua keep that is added, the hazierthe gel keep 10sh -NFCV iscosity Variation with pH in WaterDeionised water has a pH of around 5.

3 When aqua keep 10SH-NFC is added to water, the pHincreases to around and aqua keep in water was tested. The pH was varied using Potassium Hydroxide(20% dilution in water) and Citric Acid (10% dilution in water). The viscosity at varying pH wasinvestigated:At , no gel formed when the aqua keep was initially added to water. When the pH wasincreased further (even all the way to pH ), there was no gel formed. This indicates thatthere is a critical amount of aqua keep required to get gel formation, regardless of the , a gel formed when aqua keep was initially added to water. The viscosity of this gel wasaround 85,000 cP (Brookfield viscometer, T-C spindle, rpm). The pH of the initial gel was the pH was lowered, the gel broke. When the pH was increased slightly, the viscosity of thegel increased slightly.( I m not sure why aqua keep in water gave an initial pH of whereas AquaKeep gave pH The pH meter was calibrated just before testing and the pH was tested severaltimes with rinsing of the pH probe in between each test.)

4 This is in agreement with Kobo s graph where they have used aqua keep in water:% aqua KeeppHViscosity / cP(T-C spindle, rpm) gel formedThis was the pH directly after addedAqua keep to water (no pH adjuster used) gel formedSeveral drops of 20% Potassium Hydroxide wereadded, just to see what would happen at high gel formedReducing the pH broke the formed 85,000 cPThis was the pH directly after addedAqua keep to water (no pH adjuster used) formed 90,000 cPIncreasing the pH slightly increased the keep 10sh -NFCF igure 5 - Our viscosity testing using AquaKeep in water (in red text) is in agreement withthe trend from Kobo's testing using AquaKeep in water (graph).Figure 6 - aqua keep in water forms a gel with pH (uneven surface shows gel).Increasing the pH to increases the viscosity slightly (uneven surface). Lowering the pHbreaks the gel (flat surface due to the reduction in structure).

5 Figure 7 - aqua keep in waterdoes not form a gel at its initial pHof or after adjustment to keep 10sh -NFCV iscosity Variation Combined with Viscolam AT100 PLR107/16 Refreshing, Moisturising Gel uses a combination of aqua keep 10SH-NFC Viscolam AT100P s viscosity does not vary with pH, as shown by the graph below found inLamberti s brochure:As has already been discussed, the viscosity of aqua keep 10SH-NFC varies with these two facts, it is therefore not surprising that the following behaviour wasobserved when the pH of the Refreshing, Moisturising Gel was altered:At low pH (acidic conditions), the viscosity of the Refreshing, Moisturising Gel dropped; however,it still retained some viscosity . This can be explained by the viscosity from aqua keep breaking atlow pH, but the viscosity from Viscolam remaining high pH (acidic conditions), the viscosity of the Refreshing, Moisturising Gel increased can be explained by the viscosity from aqua keep increasing a little bit at increased pH, butthe viscosity from Viscolam remaining The testing on Refreshing, Moisturising Gel was qualitative not quantitative (the pH andviscosity weren t actually measured).

6 Testing involved adding citric acid to one sample of the gelin a small beaker and adding potassium hydroxide to another sample in a different beaker. Thebeakers were stirred using a spatula and the viscosity was indicated by the resistance to 8 - viscosity variation of 3% Viscolam AT100P in water. The pH stability is very wide sincethe viscosity remains relatively constant across a broad pH keep 10sh -NFCC onsidering Performance vs. pH of Skin Care FormulationsFrom the testing above, it would make sense to use a higher pH so that the content of aqua Keep10SH-NFC can be minimised to reduce , other factors have to be taken into account when creating a skin care formulation: aqua keep is most effective at pH 7 or above. Below pH 6 it provides no viscosity . Neutral pH is 7. The pH of skin is around the points above, it could be concluded that a formulation with high pH (such as abovepH 7) might be too high to use on the skin and could cause irritancy.

7 For this reason, lots of skincare products are formulated between pH However, for aqua keep to be effective, the pHshould ideally not go below pH under or around pH 7 would therefore be the optimum conditions for aqua the addition of aqua keep to water immediately gives a mixture around pH 7, it mightnot be necessary to adjust the pH; however, if there are other ingredients in the formulationthat could cause a difference in pH, it could be useful to use a pH adjuster ( with TEA,KOH or NaOH).