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Thermochromic Ink

StarColor STWB-02 Thermochromic Ink  is a high-temperature steam-activated color-changing ink specifically designed for medical packaging. It undergoes an irreversible color transition triggered by dry saturated steam.

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Product Introduction

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StarColor Thermochromic Ink SCWB-T02 is a high-temperature steam-activated color-changing ink specifically designed for medical packaging. It undergoes an irreversible color transition triggered by dry saturated steam, accurately verifying the effectiveness of sterilization processes. The ink starts in yellow, blue, or red and permanently turns black under specified sterilization conditions (e.g., 121°C dry saturated steam for 10 minutes or 134°C dry saturated steam for 4 minutes). Formulated with food-contact-grade materials, it complies with ​ISO 11140-1:2005 standards for medical indicators and is compatible with flexographic/gravure printing processes. It delivers stable color-changing performance on medical dialysis paper, coated paper, and other substrates.

​Core Technical Advantages

 ​ISO-Certified Color Change Standards

• Compliant with ​ISO 11140-1:2005 Class 1 chemical indicator requirements.
• Reliable color transition under 121°C/10min or 134°C/4min sterilization cycles.
• Irreversible color change ensures traceable sterilization validation.

 ​Process Compatibility

• Suitable for ​flexographic printing (80-150m/min).
• Recommended anilox roller: ​250-300 LPI (lines per inch for flexo).
• Low-viscosity formulation (25±5 mPa·s) for smooth application.

 ​Medical-Grade Safety

• Diluted with ​pure water; free from phthalates, heavy metals, and harmful substances.
• Post-printing residual solvents ​**<50ppm** (meets FDA standards).

 ​Color Transition System

• ​Three color options: Yellow→Black / Blue→Black / Red→Black (select initial color).
• ​Color change threshold tolerance: ±2°C.
• ​Color uniformity after reaction: ≥95%.
• ​Visual contrast: >70% (measured by CIELAB color difference ΔEab).

Technical Specifications

Parameter	Specification
Product Model	SCWB-T02
Activation Condition	121°C/10min or 134°C/4min (dry saturated steam)
Color Transition	Yellow/Blue/Red → Black (irreversible)
Printing Methods	Flexographic
Anilox Line Count	Flexo: 250-300L
Printing Speed	Flexo: 80-150m/min
Drying Condition	Hot air 45-60°C
Diluent	Purified water (5-10% addition)
Substrate Compatibility	Medical dialysis paper, coated paper labels, laminated films
Adhesion Strength	≥4B (ASTM D3359 cross-cut test)
Storage Conditions	23±2°C/50±5%RH, protected from light
Shelf Life	12 months (unopened)

 

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