Thermochromic (heat-sensitive) ink in screen, gravure and pad printing often faces: sluggish color change, wrong trigger temperature, uneven color and poor adhesion. SJH Ink shares the causes and solutions.
1. Sluggish Color Change
Caused by mismatched trigger temperature, thin ink film or low microcapsule content. Solution: choose the right trigger level (5/18°C low, 28/31/37/40°C ambient, 65/70/80°C+ high), increase film thickness and raise active microcapsule content.
2. Wrong Trigger Temperature
Batch variation, excessive oven temperature and poor storage shift the trigger point. Solution: stable batches with ±2°C tolerance, control drying temperature, avoid long-term high-temperature storage.
3. Uneven Color
Uneven film thickness, substrate absorption differences and poor dispersion. Solution: optimize leveling/dispersion, use substrate-specific formulas, adjust printing parameters.
4. Poor Adhesion
Common on smooth plastics (PVC/PC/PP/PET). Solution: corona/degrease pretreatment, matching resin systems, or a primer coat.
SJH Ink Advantages
- Custom triggers 5-80°C with ±2°C tolerance
- Reversible or irreversible
- Water-based, RoHS/REACH compliant
- Screen, gravure, flexo, pad printing on paper/plastic/metal
Shenzhen SJH Ink Co., Ltd. (est. 2002, 14 Fuxing Road, Pinghu, Longgang District, Shenzhen) offers free samples. Tel 13510998453, www.sjhink.com.