The only water-soluble sunscreen that can block UVA light (in the UVA-II range), can block UV waves in the 280-370nm range.

Disodium Phenyl Dibenzimidazole Tetrasulfonate (DPDT or Bisdisulizole Disodium) is the only water soluble sunscreen that blocks UVA light (in the UVA-II range).

Water based sunscreen spray can be developed by using Ensulizole (UVB) together with DPDT (UVA), which are water-soluble sunscreens, both types.

DPDT can be dissolved in water by using NaOH or Triethanolamine or KOH by dissolving as in this example first. and then add it to any formula

1. In case of using NaOH to dissolve

79.10% water

10% DPDT

10.90% NaOH

2. In case of using Triethanolamine to dissolve

56.70% of water

22.00% DPDT

21.30% Triethanolamine

3. In case of using KOH to dissolve

86.3% water

9.00%DPDT

4.70% KOH

Thickener/Cream Maker/Emulsifier used in product formulations using DPDT should be electrolyte resistant.

Disodium Phenyl Dibenzimidazole Tetrasulfonate (DPDT) is permitted at up to 10% in Thailand, EU, Asean, China, Australia, Brazil, South Africa.

Disodium Phenyl Dibenzimidazole Tetrasulfonate (DPDT) Not allowed in USA, Canada, Japan, Taiwan.

Instructions for use

DPDT is a fine yellow powder. The free acid is virtually insoluble in water.

By the addition of a base such as sodium hydroxide, potassium hydroxide or L-Arginine the
water soluble salts will be formed

· DPDT is strongly hygroscopic

· DPDT can be added non-neutralized to the aqueous phase of the formulation,
addition of a neutralization base with vigorous stirring will form the salt which then dissolves into
the aqueous phase

· DPDT can be also added as aqueous pre-mix

In finished formulations DPDT is stable in a wide pH range (5.0 – 9.0)
without incurring the risk of crystallization

Care has to be taken when DPDT is used in the presence of quaternary ammonium.
salts since complexes may form

Tocopherol is known to incur discoloration problems in a number of formulations;
therefore we recommend the usage of tocopheryl acetate when formulating with DPDT

DPDT is an electrolyte and therefore will have an effect upon the viscosity of
carbomer-thickened emulsions or gels. The addition of a non-carbomer derived thickening agent
such as xanthan gum and its derivatives will increase the viscosity of the formulation

Use: For any formulation that wants to protect the ingredients from the damaging effects of UV light.

Mixing method: mix in water

Usage rate:   1-10% (D.O., allowed to use no more than 10%)

Product characteristics: Yellow-Dark Yellow Powder

Solubility: can dissolve in water with the above method Please study the method of use and dissolution carefully before use.

Storage: can be stored at room temperature But close the lid of the bottle tightly. and protected from sunlight or heat, the product has a shelf life of at least 2 years

INCI Name : Disodium Phenyl Dibenzimidazole Tetrasulfonate