Heat first part of water to 75℃, add methylparaben, phosphoric acid and sodium lauryl sulfate with moderate mixing after each addition. Hold at 75℃ for five minutes.
Heat mineral oil, cetyl alcohol and ceteth-2 in separate kettle to 70℃ with stirring. Add this mixture in small increments to the aqueous phase with moderate stirring. Hold temperature at 70℃ for 15 minutes during agitation.
Carefully cool to 25℃ or room temperature. This cooling step is crucial and the optimum rate of temperature drop is I℃ per 90 seconds.
When mixture is cool, add the hydrogen peroxide and stir for 5 minutes. Adjust pH to 4.0 with phosphoric acid and make up to final volume with deionized water.
Finished Formula Properties: Appearance: White creamy emulsion pH at 25℃: 3.9-4.1 Specific Gravity at 25/25℃: 0.995-1.05 Hydrogen Peroxide: 2.38+-0.2% Max. loss after 20 hr. boil: 7%
