Pad printing Process Control Through Additives
Pad printing Process Control Through Additives
Using hardener and thinner is not just about modifying ink properties — it’s about controlling the entire pad printing process. These additives help you stabilize key variables and achieve consistent, predictable results, even when working in changing production conditions.
🔁 Finding the right balance between hardener and thinner is essential for stable print quality, especially in high-volume, pharmaceutical, and medical applications.
🔬 Why Use Hardener in Pad Printing?
Hardener plays a critical role in enhancing the durability, adhesion, and chemical resistance of pad-printed images. This becomes especially important when printing on demanding surfaces or components used in medical, pharmaceutical, or industrial environments.
🔐 Key Functions of Hardener in the Process:
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Improved Adhesion
Hardener chemically bonds with both the ink and the substrate, improving adhesion on difficult materials such as polypropylene, silicone, or metal — where regular inks may fail to stick. -
Resistance to Sterilization & Cleaning
Once cured, the ink becomes resistant to:- Autoclaving
- Alcohol-based or acidic cleaning agents
- Ultrasonic washing
This is vital for medical devices and labware that undergo harsh sterilization.
-
Abrasion and Scratch Resistance
Adding hardener increases the mechanical strength of the printed layer — important for applications like control buttons, enclosures, and measuring instruments. -
Chemical Resistance
Hardened ink can withstand oils, solvents, and other aggressive chemicals, making it suitable for industrial environments or contact with pharmaceutical substances.
⚠️ Key Considerations:
- Pot Life: Once mixed with hardener, the ink begins to cure chemically and must be used within a limited time (typically 6–8 hours).
- Dosage: Too much hardener may reduce open time and increase viscosity quickly. Too little may lead to poor durability. The typical dosage range is 5–20%, depending on substrate and ink type.
- Environmental Factors: Higher temperatures and low humidity can accelerate the curing process. Adjusting the hardener content helps maintain process stability.
And good news:
Our popular Hardener TO H is now available in a new 200 ml tube —
✅ Less waste
✅ Easier dosing
✅ Same trusted performance
✅ Better for the environment