How to check the quality of small roll thermal label paper?

Detecting the quality of small roll thermal label paper is a process involving multiple aspects, and the following are some key detection steps and methods:

1、 Sample selection and preparation

Random sampling: Randomly select a certain number of thermal paper rolls from the production batch to ensure coverage of paper from different production periods and parts.

Sample storage: Pay attention to the storage conditions of the sample and avoid affecting its initial performance due to factors such as light and humidity.

Sample integrity: The selected sample should be intact and free from obvious defects such as damage, wrinkles, or stains.

2、 Appearance inspection

Surface smoothness: Observe whether the surface of the thermal paper is smooth, without unevenness or scratches. Uneven surfaces may affect print quality, resulting in uneven color rendering or paper jams.

Color uniformity: Check whether the color of the entire roll or single thermal paper is consistent under natural light. Color differences may cause abnormal display of graphic and textual information, affecting reading and usage.

Cutting edge and roll end face: Check whether the cutting edge of the thermal paper is neat and whether the roll end face is flat and smooth.

3、 Size inspection

Length and width: Use measuring tools such as calipers and micrometers to measure the length and width of thermal paper to ensure compliance with standard requirements. Especially for small roll thermal paper, its length deviation should not exceed the specified range.

Thickness: Use a thickness gauge to measure the thickness of thermal paper, ensuring uniform thickness to ensure smooth printing and stable color development.

4、 Print quality inspection

Clarity and Resolution: Check the printing clarity, resolution, and other indicators of thermal paper by printing test samples. You can use a magnifying glass or image analysis software to measure the clarity of printed lines or points.

Color development speed: Measure the time required from heating to clear and stable color development, and the color development speed should meet practical application requirements. You can use a stopwatch for timing.

Preservability: Investigate the storage time and fading of graphic and textual information on thermal paper under different environmental conditions, such as temperature and humidity. Place the printed thermal paper under different environmental conditions and regularly observe the color changes and record them.

5、 Thermal performance testing

Thermal sensitivity: Detect the response speed of thermal paper to thermal print heads to ensure clear color development within the specified time.

Thermal stability: Evaluate the color development stability of thermal paper during continuous printing or long-term storage.

6、 Chemical performance testing

Harmful substance content: Detect the harmful substance content in thermal paper, such as heavy metals, formaldehyde, benzene, and bisphenol A, to ensure compliance with environmental requirements. Chemical analysis instruments such as high-performance liquid chromatography can be used for detection.

Chemical stability: Analyze the chemical composition of thermal paper and check whether it has changed due to environmental or time factors.

7、 Physical performance testing

Tensile strength: Use a tensile testing machine to test the tensile strength of thermal paper, ensuring that it is not easily torn during use.

Tear strength: Use a tear tester to test the tear strength of thermal paper and evaluate its durability.

Water resistance: Evaluate the color development and physical property changes of thermal paper after contact with moisture.

8、 Testing instruments and equipment

Appearance detector: used to detect the appearance defects of thermal paper.

Size measuring instrument: used to measure the size of thermal paper.

Printer: Used for printing test samples.

Thermal performance tester: used to test the thermal performance of thermal paper.

Chemical analyzer: such as high-performance liquid chromatography, used to detect the content of harmful substances in thermal paper.

Tensile testing machine and tear testing machine: used to test the tensile strength and tear strength of thermal paper.

In summary, detecting the quality of small roll thermal label paper requires comprehensive consideration of multiple aspects such as appearance, size, printing quality, thermal performance, chemical performance, and physical properties. By using scientifically rigorous testing methods and selecting appropriate instruments, the quality of thermal paper can be ensured to meet standard requirements and meet practical application needs.