Creating a formula similar to a commercial product like MizuMi UV WATER SERUM involves understanding the function of each ingredient and selecting suitable alternatives or equivalents available. Replicating a formula exactly can be challenging due to specific grades of raw materials and manufacturing processes, but you can certainly create a formula with similar characteristics and performance.

Based on the ingredient list you provided for MizuMi UV WATER SERUM and the products available, here's a breakdown and some recommendations:

Key Ingredients and MySkinRecipes Equivalents:

• UV Filters: Zinc Oxide and Titanium Dioxide are the physical UV filters. For a lightweight serum, using pre-dispersed liquid forms is highly recommended for ease of use, better dispersion, and reduced whitening effect compared to powders.
  • Suggested Products: Consider Zinc Oxide dispersions like Zinc Oxide 35nm Liquid or Zinc Oxide Transparent Dispersion (C12-15 alkyl benzoate Base), and Titanium Dioxide dispersions like Titanium Dioxide Nanosil or Titanium Dioxide Transparent (15nm, Water-Dispersion).
• Emollients & Solvents: Ingredients like Isododecane and Neopentyl Glycol Diheptanoate provide a light, non-greasy feel and help disperse UV filters.
  • Suggested Products: Isododecane (Germany) and Neopentyl Glycol Diheptanoate.
• Humectants: Butylene Glycol, Propanediol, Methylpropanediol, and Methyl Gluceth-20 help hydrate the skin and contribute to the serum texture. Sodium Hyaluronate is a well-known humectant.
  • Suggested Products: Butylene Glycol, Propanediol (1,3-Propanediol), Methylpropanediol, Methyl Gluceth-20, and Hyaluronic Acid Gel Base (which contains Sodium Hyaluronate).
• Emulsifiers: The MizuMi list includes several emulsifiers (Dioctyldodeceth-5 Lauroyl Glutamate, Glyceryl Stearate, Steareth-21, Steareth-2, PEG-100 Stearate). A combination is often used to create a stable emulsion, especially with a high load of physical filters.
  • Suggested Products: Glyceryl Stearate and PEG-100 Stearate (Powder), Steareth-2, and Steareth-21 are available options. You may need to experiment with ratios and potentially other emulsifiers to achieve the desired stability and texture.
• Thickeners & Stabilizers: Ammonium Acryloyldimethyltaurate/VP Copolymer, Carbomer, and Xanthan Gum help create the serum's viscosity and stabilize the UV filter dispersion.
  • Suggested Products: Aristoflex AVC (Ammonium Acryloyldimethyltaurate/VP Copolymer), Carbomer 940 (EasyDisperse™, France), and Xanthan Gum (clear gel type, smooth texture).
• Antioxidants: Ascorbyl Tetraisopalmitate and DL-alpha-tocopheryl-acetate protect the formula and skin from oxidation.
  • Suggested Products: Perfect-C™ (Ascorbyl Tetraisopalmitate) and Vitamin E (Tocopheryl Acetate).
• Preservatives: Caprylhydroxamic Acid and Phenoxyethanol are listed.
  • Suggested Products: Caprylhydroxamic Acid and Phenoxyethanol (Extra Pure). Mild Preserved Eco™ (containing Ethylhexylglycerin and Propanediol) is another relevant preservative option mentioned in your example formula.
• Other Additives: Alumina can improve texture and slip. Simethicone is an anti-foaming agent. Triethanolamine is a pH adjuster, often used to neutralize Carbomer.
  • Suggested Products: Alumina (5micron, Spherical), Simeth-15 (Simethicone Anti-Foaming), and Triethanolamine 99%.

Formulation Considerations:

Creating a stable physical sunscreen serum requires careful formulation. Key steps generally involve:

1. Properly dispersing the physical UV filters in a suitable carrier (often oil or silicone phase). Using pre-dispersions simplifies this.
2. Creating a stable emulsion system that can hold the dispersed solids and oil phase within the water phase. This often requires a blend of emulsifiers and sufficient thickening/stabilizing polymers.
3. Incorporating humectants and emollients for desired skin feel and hydration.
4. Adding sensitive ingredients like vitamins and preservatives in the cool-down phase.
5. Adjusting pH for stability and efficacy.
6. Adding Alumina and Simethicone for texture and anti-foaming.

Regarding the Example Formula Question:

You asked if the example W/O sunscreen formula using Zinc Oxide 35nm Liquid and Titanium Dioxide 15nm Liquid needs an additional emulsifier, noting that Cyclomethicone is oil-soluble and the oxides are mixed in it before adding to water.

The example formula likely relies on the emulsifying agents that are already present within the "liquid" forms of the Zinc Oxide and Titanium Dioxide. These liquid products are typically pre-dispersions where the solid UV filter particles are coated and suspended in a carrier fluid (like Cyclomethicone or other oils/silicones) along with dispersing agents and often emulsifiers specifically chosen for creating stable emulsions, sometimes water-in-oil emulsions as suggested by the formula title mentioning Water-in-Oil Cream.

Therefore, in that specific example formula, the emulsification is primarily handled by the components within the Zinc Oxide 35nm Liquid and Titanium Dioxide 15nm Liquid dispersions, potentially aided by a dedicated W/O emulsifier like Water-in-Oil Cream if that product is incorporated as suggested by the title. You would typically not need to add a separate, additional emulsifier if using these pre-dispersed systems designed for W/O emulsions. The Cyclomethicone acts as a carrier and contributes to the texture of the oil phase.

In Summary:

To create a physical sunscreen serum similar to MizuMi, focus on using high-quality dispersed physical filters, a robust emulsification system (likely a blend), effective thickeners/stabilizers for the serum texture, and a combination of emollients and humectants for skin feel. The example formula you saw uses a W/O approach with pre-dispersed oxides, where the emulsifiers are part of those dispersions.

Here are some relevant products from MySkinRecipes based on the MizuMi ingredient list and your query:

• Zinc Oxide (Micronized)
• Zinc Oxide 35nm Liquid
• Titanium Dioxide Nanosil
• Isododecane (Germany)
• Neopentyl Glycol Diheptanoate
• Butylene Glycol
• Propanediol (1,3-Propanediol)
• Alumina (5micron, Spherical)
• Aristoflex AVC
• Caprylhydroxamic Acid
• Glyceryl Stearate and PEG-100 Stearate (Powder)
• Steareth-21
• Steareth-2
• Phenoxyethanol (Extra Pure)
• Methylpropanediol
• Simeth-15 (Simethicone Anti-Foaming)
• Methyl Gluceth-20
• Triethanolamine 99%
• Carbomer 940 (EasyDisperse™, France)
• Perfect-C™ (Ascorbyl Tetraisopalmitate)
• Vitamin E (Tocopheryl Acetate)
• Xanthan Gum (clear gel type, smooth texture)
• Hyaluronic Acid Gel Base
• Mild Preserved Eco™

Experimentation with ingredient percentages and mixing procedures will be necessary to achieve the desired texture, stability, and SPF/PA rating.