In DTF printing production, air purification systems play a critical role not only in maintaining a cleaner working environment but also in ensuring equipment reliability and operator safety. As a one-stop manufacturer of DTF digital printing solutions, Hanrun has long been committed to advancing air purification technologies for the DTF industry.
To meet the needs of different production environments and business scales, Hanrun offers both integrated purification solutions (primarily the Super Series) and external purification solutions (primarily the PRO Series).
Hanrun's Super Series powder shaker machines integrate air purification and smoke condensation systems into a single unit, effectively removing oil fumes while minimizing oil leakage risks. The all-in-one design eliminates the need for external purification equipment, making it an ideal solution for customers seeking energy efficiency, space savings, and a higher level of automation.
During customer support and field applications, Hanrun identified a common issue affecting external purification systems: condensate backflow caused by cooling smoke inside long exhaust pipelines. To address this long-standing industry challenge, Hanrun leveraged its extensive industry experience and R&D capabilities to develop an innovative anti-backflow device with independent intellectual property rights, providing a more reliable solution for stable DTF production.
In a typical DTF production environment, high-temperature smoke generated during the curing process is transported through ducts to an air purification system. As the smoke travels through the pipeline, its temperature gradually decreases. Oil particles and moisture within the smoke begin to condense, forming sticky liquid residues.
Under certain airflow conditions or pipeline configurations, these condensates may flow back toward the printing equipment, potentially causing:
• Printhead contamination or clogging
• Carbon buildup inside equipment
• Increased risk of electrical short circuits
• Reduced print quality
• Higher maintenance frequency and operating costs
• Unplanned production downtime
This issue has existed throughout the industry for years and continues to impact production stability.
Traditional purification systems focus primarily on smoke extraction and filtration. However, they generally lack dedicated designs to address condensation and backflow during smoke transportation, making it difficult to eliminate the problem at its source.
To overcome this challenge, Hanrun Paper's affiliated company, Nanjing Zezhichen Digital Technology Co., Ltd., filed a utility model patent application on June 12, 2025:
Patent Title:Device for Preventing Smoke Backflow Caused by Pipeline Cooling
Authorization Announcement No.:CN224322049U
Authorization Date:June 5, 2026

Patent No.:ZL202521198047.3
The patent includes seven claims, eight pages of technical specifications, and five pages of engineering drawings, demonstrating a complete and highly practical technical solution.
The anti-backflow device improves smoke transportation through three key innovations:
A specially designed check-valve structure ensures that smoke can only travel toward the purification unit, effectively blocking any reverse airflow path.
Dedicated condensate collection components capture and divert liquid residues before they can enter the printer or powder shaker, preventing contamination and damage.
By reducing temperature fluctuations within the exhaust system, the design minimizes condensation formation at the source.
Together, these technologies create a comprehensive anti-backflow protection system.
In real-world production environments, this technology can provide:
• Reduced printhead clogging and equipment failures
• Less corrosion and contamination of internal components
• Extended equipment service life
• Lower maintenance and replacement costs
• Improved production continuity and efficiency
Ultimately, it enhances the overall stability, reliability, and controllability of DTF production operations.
Hanrun Paper and its affiliated company, Nanjing Zezhichen Digital Technology Co., Ltd., have accumulated 34 patent applications and 20 certifications, testing reports, and software copyrights, totaling 54 intellectual property and qualification assets.
These achievements support a comprehensive intellectual property portfolio covering the entire digital printing workflow, including DTF printing, UV printing, and Sublimation printing.
The successful implementation of this anti-backflow patent further strengthens equipment reliability and represents another important milestone in Hanrun's ongoing efforts to solve real-world industry challenges through innovation.
As competition within the industrial digital printing market continues to intensify, Hanrun paper remains committed to improving product performance through engineering innovation, structural optimization, and continuous technological advancement.
Looking ahead, Hanrun paper will continue investing in research and development to further enhance DTF equipment and supporting systems, delivering more mature, efficient, and reliable solutions that contribute to the sustainable growth of the industry.
Facebook:https://www.facebook.com/HanrunpaperOfficial/
Youtube:https://www.youtube.com/c/Hanrunpaper
Instagram:https://www.instagram.com/hanrunpaper/
Linkedin:https://www.linkedin.com/company/hanrunpaper/
Whatsapp:+86 189 3686 5061