Dicyandiamide is rarely added directly as powder in papermaking; it is mostly formulated into dicyandiamide-formaldehyde resin (DDF), and direct powder addition is only adopted for a small number of specialty papers.

1. Wet Strength Agent (Napkins, Hand Towels, Wet-strength Packaging Paper)

   Form: Liquid resin synthesized from dicyandiamide and formaldehyde

   Dosage: 1.5%–4.0% based on oven-dry fiber

   Dosing point: Before fan pump / headbox

   Process conditions: pH 4.5–6.5, dryer temperature ≥105℃ for curing

   Effect: Greatly improves wet strength; contains trace formaldehyde, not recommended for high-grade food-contact paper.
2. Retention & Drainage Aid (Cultural Paper, High-filler Paper)

   Form: Modified dicyandiamide resin (MDDF)

   Dosage: 0.02%–0.08% based on oven-dry fiber (0.03% for normal use)

   Function: Improve filler retention, reduce white water loss, accelerate dewatering, boost paper opacity
3. Direct Powder Addition (Specialty Papers Only)

   Applicable products: Transformer insulating paper, high-temperature resistant interleaving paper

   Operation: Dissolve powder in 40–50℃ warm water, then add to stock chest

   Dosage: 0.3%–1.0% based on oven-dry fiber

   Function: Anti-aging, stabilize insulating performance, high temperature resistance
4. Papermaking Wastewater Treatment (Decolorization & COD Reduction)

   Agent: Dicyandiamide-formaldehyde decolorizing liquid

   Operation: Dilute with water 10–40 times, add to flotation tank / primary sedimentation tank

   Dosage: 0.5‰–3‰ of wastewater volume
5. Key Precautions

• Dicyandiamide powder hardly dissolves in cold water; dissolve with warm water and prepare before use

• Resin products are unstable under strong alkaline conditions, stable in acidic & weak neutral systems

• Resins containing formaldehyde shall not be used for high-grade food-contact paper

• Liquid resins should be sealed and stored in cool places, protected from freezing