The Single-Sided Treatment Sheet Corona Treater is a key piece of equipment in plastic film printing, primarily used to enhance the adhesion of inks, coatings, and adhesives. Its principle involves treating the surface of plastic films through high-voltage discharge to break down the original molecular structure, improving surface properties from both physical and chemical perspectives. This lays a foundation for subsequent printing processes and prevents quality issues such as ink peeling or delamination caused by the surface characteristics of the film. The Single-Sided Treatment Sheet Corona Treater has a processing speed of 5-400 meters per minute (customizable upon request) and a processing width of 300-3000 millimeters (customizable upon request). Additionally, the single-sided sheet corona treatment process eliminates the complex preheating and debugging procedures during the startup cycle.
Core Information
The Single-Sided Treatment Sheet Corona Treater is indispensable in plastic film printing because plastic films (e.g., PP, PE) are non-polar materials with low surface tension, making it difficult for inks and glues to adhere without treatment. Its core principle is to generate corona discharge using high-frequency and high-voltage electricity, forming low-temperature plasma. This process increases surface roughness through physical etching and introduces polar groups (e.g., hydroxyl, carboxyl groups) through chemical modification, collectively improving surface energy.
The treatment effect is commonly tested using a dyne pen, requiring a surface tension of ≥38 mN/m, or measured in accordance with the DIN ISO 8296 standard. To ensure adhesion stability, the surface tension of the film must be approximately 10 dynes higher than that of the ink. However, the treatment effect will diminish over time, mainly due to the migration of additives and the reduced activity of polar groups, so the production process must be arranged reasonably.
Key parameters include the discharge gap (optimally 1-2 mm; a gap that is too small may puncture the film, while a gap that is too large results in insufficient effectiveness) and processing power (which must be matched to the production line speed, film material, and width). Insufficient power leads to inadequate modification, while excessive power may damage the film or waste energy. Environmental factors such as high air humidity can weaken the treatment effect, especially during humid seasons, requiring enhanced monitoring and parameter adjustments to compensate.
Operation Tips
The key to operating the Single-Sided Treatment Sheet Corona Treater lies in achieving precise matching between parameters and requirements, as well as balancing treatment effectiveness and film protection. Specifically, it is necessary to adjust the device's power and electrode gap based on four factors:
Film type: Different materials (e.g., PP, PE, PET) have distinct molecular structures, requiring adjusted treatment intensity (e.g., PET films have slightly higher molecular polarity than PP films, allowing for slightly lower processing power).
Printing process requirements: Different ink types (e.g., solvent-based, water-based, UV-curable) have varying surface energy requirements (e.g., water-based inks require higher surface energy).
Production environment: Changes in humidity directly affect effectiveness; higher humidity requires a moderate increase in power.
Production speed: Faster speeds reduce the film's residence time in the treatment area, necessitating increased power to ensure sufficient reaction.
The goal is to meet the surface tension standards required for printing while avoiding film embrittlement or deformation caused by over-treatment, achieving both functional performance and protective effects.
Practical Operation Advice for Beginners
For beginners, priority should be given to "hot film" online treatment-i.e., treating the film directly on the plastic film production line. At this stage, the film's molecules have high activity, enabling ideal modification without excessive power, and the surface energy remains more stable after treatment.
Second, strengthen secondary verification and supplementary treatment of the effect: Before printing, use a dyne pen to test the film's surface tension and ensure it meets requirements. For films stored for more than 72 hours, films with diminished surface energy, or scenarios requiring high surface energy (e.g., using water-based inks), supplementary treatment is necessary (e.g., using offline equipment or a supplementary treatment device installed in front of the printing machine).
In daily operations, dynamically monitor the environment and keep track of workshop humidity (recommended 40%-60% RH). Increase the frequency of testing during humid seasons; if surface tension decreases, moderately increase power (adjust by no more than 5% each time) or reduce the discharge gap (minimum 1 mm) to maintain stable treatment effectiveness.
Most importantly, strictly adhere to high-voltage safety regulations: Before starting the device, check that grounding is in place (ground resistance ≤4 Ω) and regularly inspect the insulation of high-voltage lines. Non-professionals are prohibited from opening the high-voltage compartment; during maintenance, cut off the power supply and discharge residual electricity. Install warning signs in the operation area to prevent unauthorized personnel from entering, ensuring safety.
All products are made in China. The Single-Sided Treatment Sheet Corona Treater strictly adheres to the quality management system for production and inspection, supports wholesale and bulk purchasing, and provides customized services.