Lesson 1Humectants: examples (glycerin, propanediol, sodium PCA), mechanism and suitability for sensitive skinDis section analyze humectants such as glycerin, propanediol, and sodium PCA, describing water-binding mechanisms, synergy in blends, impact pon skin feel, and how fi tailor humectant systems fi sensitive or compromised barriers.
Glycerin: benchmark humectant behaviorPropanediol and alternative glycolsSodium PCA and NMF-mimicking blendsTack reduction and sensory balancingHumectants in barrier-impaired skinLesson 2Antioxidants and chelators: examples (tocopherol, EDTA), role in oxidative stability and preservationDis section explain how antioxidants and chelators, including tocopherol and EDTA, protect oils and actives from oxidation, support preservative systems, and extend shelf life widout compromising skin comfort or clarity.
Lipid-phase antioxidants fi oilsWater-phase antioxidants and synergyChelators to control trace metalsImpact pon color and odor stabilityDesigning antioxidant systems in O/WLesson 3Occlusives: examples (dimethicone, hydrogenated polyisobutene), balancing occlusion and light feelDis section discuss occlusives such as dimethicone and hydrogenated polyisobutene, showing how fi balance barrier reinforcement, transepidermal water loss reduction, and a light, breathable feel suitable fi daily sensitive skin care.
Dimethicone grades and skin feelHydrogenated polyisobutene in creamsTEWL reduction and barrier metricsAvoiding heaviness and pore occlusionOcclusive levels fi day versus nightLesson 4Soothing/anti-irritant actives: examples (niacinamide, panthenol, dipotassium glycyrrhizate), evidence and typical use rangesDis section examine soothing and anti-irritant actives such as niacinamide, panthenol, and dipotassium glycyrrhizate, summarizing mechanisms, supporting evidence, compatibility, and typical use ranges in sensitive skin moisturizers.
Niacinamide: barrier and redness benefitsPanthenol: hydration and repair rolesDipotassium glycyrrhizate: calming actionUse levels and pH compatibilityCombining soothing actives safelyLesson 5Core functional groups for O/W moisturizer: role of solvent, humectant, emollient, occlusive, emulsifierDis section map de core functional groups in O/W moisturizers—solvents, humectants, emollients, occlusives, and emulsifiers—showing how each contribute to feel, hydration, stability, and tolerance in sensitive skin formulations.
Water phase and co-solvent selectionHumectant blend design and levelsEmollient phase structure and feelOcclusive agents and barrier supportEmulsifier system and phase balanceLesson 6Preservative systems for mild formulas: examples (phenoxyethanol+ethylexylglycerin, sodium benzoate+potassium sorbate), rationale for sensitive skinDis section review preservative systems suited to mild O/W moisturizers, such as phenoxyethanol wid ethylhexylglycerin and organic acid salts, focusing pon spectrum, pH needs, regulatory limits, and sensitive skin tolerability.
Phenoxyethanol and boosters in blendsSodium benzoate and potassium sorbatepH windows fi organic acid systemsPreservative efficacy versus mildnessMinimizing sting and sensitization riskLesson 7Emollients: examples (caprylic/capric triglyceride, C12-15 alkyl benzoate), sensory and absorption considerationsDis section explore emollient choices such as caprylic/capric triglyceride and C12-15 alkyl benzoate, linking chemical structure to spread, absorption rate, residue, and suitability fi lightweight, non-greasy sensitive skin creams.
Medium-spreading esters and triglyceridesFast-absorbing versus rich emollientsPolarity and pigment or filter wettingTack, gloss, and afterfeel controlEmollient choices fi acne-prone skinLesson 8Solubilizers, pH adjusters, and texture modifiers: examples and impact on performanceDis section review key solubilizers, pH adjusters, and texture modifiers used in O/W moisturizers, explaining how dem influence clarity, viscosity, spreadability, and overall performance while maintaining comfort pon sensitive skin.
Nonionic solubilizers fi fragrance and oilspH adjustment fi skin compatibilityBuffers and pH drift controlRheology modifiers and viscosity tuningSlip, spread, and pick-up optimizationLesson 9Common incompatibilities and ingredient substitution strategiesDis section cover common incompatibilities in O/W moisturizers, including pH, charge, and oxidation issues, and present practical substitution strategies to maintain stability, mildness, and performance when changing suppliers or actives.
pH-driven instability and hydrolysisCationic–anionic charge conflictsOxidation-prone oils and activesPreservative and polymer conflictsDesigning robust substitution plansLesson 10Emulsifiers and co-emulsifiers: examples (polyglyceryl esters, glyceryl stearate SE), HLB considerations and mildnessDis section detail emulsifiers and co-emulsifiers, including polyglyceryl esters and glyceryl stearate SE, explaining HLB concepts, required HLB of oil phases, and how fi design mild, stable systems fi sensitive skin moisturizers.
Required HLB of de oil phaseNonionic emulsifiers fi mildnessPolyglyceryl esters in O/W systemsFatty alcohols as co-emulsifiersOptimizing droplet size and stability
