Which type of adjuvant increases the viscosity of spray mixtures?

• A. A Surfactants
• B. B Emulsifiers
• C. C Thickeners
• D. D Wetters

Answer: (C)

Viscosity is about how thick a liquid is and how much it resists flow. Thickeners are additives designed to increase that thickness in spray mixtures. By forming a more viscous solution, they slow movement, help droplets stay intact longer, and can reduce drift while improving coverage and suspension of components in the mix.

Surfactants and emulsifiers, on the other hand, modify how liquids interact at surfaces and between immiscible phases. Surfactants reduce surface tension to improve wetting and spreading; emulsifiers help keep oil and water phases mixed. Wetters are compounds that often function as surfactants to enhance wetting. None of these primarily change how thick the liquid is, which is why they don’t increase viscosity.