Drying Technology in ODF: Key to Film Stability and Quality

In the production of Oral Dissolvable Films (ODF), drying is more than a physical process—it’s a critical factor that influences product quality and stability. Parameters like drying speed, temperature gradients, and airflow paths directly impact film uniformity, active ingredient distribution, and final product consistency.

Why Is Drying So Crucial in ODF Manufacturing?

Unlike tablets or capsules, ODFs contain minimal moisture. Even slight deviations in drying can lead to:

• Incomplete film formation—causing cracks or wrinkles
• Migration of active ingredients—leading to dose inconsistency
• Sticky or fragile films—making cutting and packaging difficult
• Compromised shelf life—due to poor long-term stability

That’s why a well-designed drying process is essential to ensure that ODFs are easy to handle, store, and deliver accurate dosage.

Common Drying Techniques for ODF

1. Hot Air Convection Drying: The most common method, cost-effective and suitable for general ODF lines.
2. Infrared/Far-Infrared Heating: Ideal for temperature-sensitive APIs, accelerates drying efficiency.
3. Vacuum or Low-Temperature Dehumidification: Best for high-value or moisture-sensitive formulas—though more costly.

Huanghai’s Approach: Gradient Drying for Stability

Our equipment features a hot air drying tunnel with optimized duct length and airflow paths. This design naturally forms a temperature gradient—from high to low—ensuring gentle transitions that preserve membrane integrity and reduce internal stress.

How to Evaluate Drying Quality?

To ensure drying success, we recommend measuring:

• Film thickness consistency (to check for uneven drying)
• Content uniformity (to ensure even API distribution)
• Residual solvent levels (especially for solvent-based formulations)
• Low-temperature storage stability (to simulate shelf-life conditions)

Conclusion

Drying process design is not only crucial for manufacturing efficiency but also for regulatory compliance and market acceptance. Manufacturers should prioritize equipment with adjustable temperature zones, balanced airflow, and stable tension control—paired with robust quality detection tools for a closed-loop production system.

For a full overview of the certifications and compliance standards our equipment meets, see our Certifications & Compliance page.

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Frequently Asked Questions

Q: What is the difference between an ODF film and a transdermal patch?

A: Oral Dissolving Films (ODF) are placed on or under the tongue and dissolve within seconds to minutes, delivering APIs directly through the oral mucosa or via swallowing. Transdermal patches adhere to the skin and deliver APIs through the dermal layers into systemic circulation over hours to days. Despite different delivery routes, both are manufactured using similar solvent-cast film coating processes. Huanghai's MJ150 ODF machine supports both applications on a single platform with approximately 2 working days of changeover time.

Q: What production output can I expect from a Huanghai ODF machine?

A: The MJ150 produces 20,000 films/hour at commercial scale. The MJ150-L targets R&D and pilot production at 8,000–10,000 films/hour. For fully integrated lines, pair either machine with the MJF180 automatic cutting and packaging system (11,900 films/hr) or the more affordable EZ320 (9,000 films/hr). A complete MJ150 + MJF180 line can produce over 150 million finished pouches annually on a single-shift basis. Contact us for pricing and configuration details.

Q: What drying technology does Huanghai use for ODF production?

A: Huanghai uses patented gradient hot-air drying (Patent CN201668734U), which applies a smooth progressive temperature drop rather than stepwise oven zones used by competitors. This results in more uniform film thickness, reduced edge curl, and better API distribution across the film web. An optional far-infrared heating module adds 20–30% drying efficiency for solvent-based formulations. This patented drying system is one of the key technical advantages that justifies Huanghai's position as the preferred ODF equipment supplier to Sinopharm, Shanghai Pharma, and Fosun Pharma.

Q: What are the GMP requirements for ODF production equipment?

A: ODF manufacturing equipment must comply with cGMP (21 CFR Parts 210/211) for US market products, and equivalent standards (EU GMP Annex 1, ChGMP) for other markets. Key requirements: material contact surfaces must be 316L stainless steel or equivalent; CIP/SIP capability or documented cleaning validation; data integrity controls meeting ALCOA+ principles (audit trails, access control). Huanghai ODF machines meet these standards—all product contact surfaces use pharmaceutical-grade materials, and the control system includes operator access logs and parameter change records. Request our GMP compliance documentation.

Q: Can Huanghai machines produce stripe-coated or multi-formula ODF films?

A: Yes. Huanghai holds a patent for multi-formula stripe coating (Patent CN117323228A), enabling two different API formulations to be applied side-by-side in a single coating pass. This eliminates the need for multiple coating/drying cycles when producing combination-drug ODF products. Competitors require manual multi-layer coating with drying intervals between each formula. This capability is particularly valuable for fixed-dose combination products (e.g., dual-API ODFs for cardiovascular or CNS indications) where coating efficiency directly impacts production economics.