1,3-dichloro-5,5-dimethylhydantoin

1,3-Dichloro-5,5-dimethylhydantoin (CAS 118-52-5), known as DCDMH, is a solid chlorine-donor compound used industrially as a controlled-release biocide and bleaching agent. Also marketed as Dactin and Halane.

Where is 1,3-dichloro-5,5-dimethylhydantoin used?

• Water treatment: controls microbial growth in cooling towers and industrial process water
• Swimming pools: releases available chlorine at a controlled rate
• Pulp and paper: bleaching agent for consistent whiteness targets
• Personal care: preservation booster and antimicrobial active in rinse-off products
• Food processing: sanitizing agent for equipment and surface disinfection within strict regulatory limits
• It delivers active halogen in a stable, measurable form suited to demanding process environments.

Good to know: Unlike liquid chlorine sources, it delivers active halogen in a stable, measurable form; it avoids the dangers of gaseous chlorine while maintaining high efficacy. It is particularly useful where residual biocidal activity is required.

Commercial specifications

• Specifications aligned to active chlorine content and moisture limits for stability
• Packaging from small drums to bulk quantities