Comparison Method for Long-Term Preservation Performance of Thermal Paper

Core: Uniform printing → Uniform aging → Uniform testing → Quantitative scoring and ranking, controlling variables and comparing only the paper itself.

I. First, do 3 "uniform" things (key):

1. Uniform printing: Use the same thermal printer, the same speed, and the same environment;

Print: Solid black block + text + barcode, ≥3 samples per group.

2. Uniform initial testing: Measure: Blackness OD value, color difference ΔE, and record the initial values.

3. Standardized Aging Conditions (Choose one or all three)

- Option A (Rapid Testing): 60℃/90%RH constant temperature and humidity 24–72h

- Option B (Lightfastness): Xenon lamp/UV aging 48–72h

- Option C (Simulated Room Temperature): Store in the dark for 1–3 months

II. Comparative Testing Indicators (Direct Scoring)

1. Blackness Retention Rate

Retention Rate = OD after aging / Initial OD × 100%

→ Higher is better

2. Color Difference ΔE

The larger the ΔE, the more severe the yellowing/discoloration

→ The smaller the better

3. Handwriting Clarity

Visual inspection + barcode scanning: Is it blurry, has broken strokes, or faded?

→ Barcode can be scanned and text is legible, indicating it is acceptable.

4. Paper Surface Condition

Is it sticky, clumped, curled, or shedding powder?

→ No abnormalities are good.

III. Quick Comparison Scoring Table (Can be used directly)

Item Scoring Standard Sample 1 Sample 2 Sample 3 Blackness Retention Rate: ≥90% = 10 points, 70-90% = 5 points, <70% = 0 points

Color Difference ΔE: ≤3 = 10 points, 3-5 = 5 points, >5 = 0 points

Clarity: Clear and scannable = 10 points, Slightly faint = 5 points, Blurry = 0 points

Paper Surface: Normal = 10 points, Slight = 5 points, Severe = 0 points

Total Score

IV. Conclusion Judgment

- Total Score ≥35: Excellent, suitable for long-term archiving

- 25–34: Satisfactory, suitable for short-term/regular use

- <25: Poor, not recommended for archiving