Dispersing Agent for Sunscreens Dispersun DSP-OL100 and DSP-OL300

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1 Dispersing Agent for Sunscreens OL1 and DSP-OL3 INCI Name: Polyhydroxystearic acid CAS No.: EINECS No.: OL1 OL3 OL1 and DSP-OL3 are highly effective dispersants for ultrafine titanium dioxide and zinc oxide. Both products can significantly increase UV absorption of sunscreens containing pigments, in addition to reducing whitening when applied to skin. They dramatically decrease viscosity of dispersions at dose rates of just a few percent, allowing higher concentrations of pigment to be used. They significantly improve optical transparency and UV absorption, which enables cost savings to be made due to using lower pigment levels. APPLICATIONS Alternatively higher sun protection factor (SPF) sunscreen can be made without increasing pigment levels. Performance Properties Increased pigment loading Better UV absorption Suncreens Moisturizers Barrier creams Lip protectors Baby products Potential for higher sun protection factor SFP Allows use of untreated Zinc oxide in alkybenzoate Improved transparency Lower viscosity Improved stability dispersions Natural origin Reduced milling time Compatible with other sunscreen components Mechanism Dispersun DSP dispersants bind to the surface of inorganic sunscreen particles preventing their mutual attraction by steric repulsion, hence giving finer particle size.

2 Test Data Better UV absorption Dispersun dispersants give an increase in UVB absorbance with TiO2 and a decreased absorbance (i.e. improved transparency) in the visible region. Absorbance in the UVA region is dramatically increased when Dispersun dispersants are used for untreated zinc oxide in alkylbenzoate. UV- Visible Absorption Curves for TiO2 (.25% pigment) (Beadmilled dispersion in C12-C15 alkylbenzoate diluted in mineral oil). 1.9 UVB Region UVA Region Visible Region.8.7 Absorbance Wavelength (nm) No dispersant OL 1 OL 3 UV-visible absorption curves for ZnO (.75% pigment) (Beadmilled dispersion in C12-15 alkyl benzoate diluted in mineral oil) UVB Region UVA Region Visible Region Absorbance No Dispersant Dispersun DSP OL-1 Dispersun DSP OL-3 Wavelength (nm)

3 Improved transparency Dispersun dispersants improve transparency with TiO2 as shown by the drawdown. TiO 2 No dispersant TiO 2 With Dispersun (2% solids) DSP-OL3 (2% solids) Lowers viscosity A dispersant demand curve is used to determine the optimum concentration of dispersant for a given pigment. This type of experiment allows the optimum dispersant level to be estimated. Adding OL1 and DSP-OL3 shows a dramatic decrease in viscosity. Adding OL1 or DSP-OL3 causes a dramatic decrease in viscosity. Due to varying processing methods, the viscosity for bead milled dispersions will be different to these shown. 3 Rheology Curve for Titanium Dioxide in C 12 -C 15 Alkylbenzoate (Containing 5% pigment solids, 7rpm stirrer). 25 Viscosity (mpa.s) OL1 OL % Dispersant added (based on pigment weight) TiO2 grade = Tayca MT1TV (15nm, coated with Aluminium Hydroxide and Stearic Acid

4 Rheology Curve for Zinc Oxide in C 12 -C 15 Alkylbenzoate (containing 65% pigment solids, 7rpm stirrer) Viscosity (mpa.s) OL1 OL % Dispersant added (based on pigment weight) ZnO grade = BASF Z-Cote (2nm, uncoated) Increased pigment loading These dispersions were bead milled to a fine grind and demonstrate that pigment solids content can be more than doubled using Dispersun dispersants, while effectively controlling viscosity. TiO 2 ZnO Solids (%) Viscosity (mpas) Solids (%) Viscosity (mpas) No Dispersant 25 Too thick to process 2 73 With¹ OL [8]¹ 65 8 [3.4]¹ ¹. [Percentage weight on pigment]

5 Improved milling time Dispersun dispersants allow shorter milling times and hence improved ultimate fineness of grind. 12 Particle size against time for Titanium dioxide dispersions. (Beadmilled dispersions). 1 8 Hegman reading (µ) No dispersant DISPERSUN DSP- OL Time (mins) Recommended Use Directions Dispersant should be dissolved in the carrier phase (e.g. alkylbenzoate) before adding pigment. The dispersant should be warmed and stirred before use to ensure a homogeneous product. The dose rate needs to be optimised for each pigment grade. One way of doing this is a dispersant demand curve. The recommended starting dose rate would normally be the amount of dispersant required for the minimum viscosity plus about 25% extra. Final optimisation of dispersant dose must be carried out by milling dispersions on equipment that represents production. Packaging Available in 2kg and 17kg drums. For further information, please your region: Americas: americas-ac@innospecinc.com Europe, Middle East and Africa: emea-ac@innospecinc.com Asia-Pacific: aspac-ac@innospecinc.com The facts stated and the recommendations made are based on our own research and/or the research of others, and are believed to be accurate. No guarantee of their accuracy is made, however, and unless otherwise expressly provided by law or in written contract, the materials are sold without warranties, expressed or implied, in particular without guarantee as to suitability for particular purpose. Innospec assumes no responsibility for injury or damage to users or third parties. Recipient agrees to assume all risk and liability whether used singly or in combination with other materials. Issue No. 4 /21