How to determine if PET thermal sensitive silver paper has expired?

To determine whether PET thermal sensitive silver paper has expired, the following aspects can be taken into account:

1、 Observe the appearance of the paper

Color: High quality PET thermosensitive silver paper should have a slight greenish tint instead of being too pure white. If the paper color is too pale, it may indicate that too much fluorescent powder has been added to the paper, or that the protective coating and thermal sensitive coating are not properly configured, which can affect the quality and shelf life of the paper.

Smoothness and Uniformity: Carefully observe the smoothness and uniformity of the paper. If the surface color is uneven, it may indicate that there are deficiencies in the production process of the thermosensitive layer and protective layer, which in turn affects the overall quality of the paper.

2、 Use the fire roasting method for detection

Operation method: Place the back of the paper on the fire and gently bake it, observing the color change after heating.

Judgment criteria:

If the paper turns brown, it usually indicates poor quality of its thermal sensitive material and may have a shorter storage time.

If the color appears black green and uniform, it indicates that the paper is of high quality and has a longer shelf life.

3、 Identification through natural light exposure

Operation method: Apply the printed paper with the same fluorescent pen and let it sit in the sun for natural exposure.

Judgment criteria:

Observe the time when the paper turns black. The longer it takes to turn black, the longer the storage time of this thermal paper.

If the paper turns black quickly, it may mean that its storage time is shorter.

4、 Check packaging and labeling

Check production date and shelf life: If PET thermosensitive silver paper has clear production date and shelf life markings, you can directly determine whether the paper has expired based on this information.

Observe whether the packaging is intact: Paper with damaged or damp packaging may affect its storage time and quality.

5、 Consider storage conditions

The storage time of PET thermosensitive silver paper is also affected by storage conditions. If paper is exposed to moisture, high temperatures, and direct sunlight for a long time, its storage time and quality may be greatly reduced. Therefore, when determining whether a paper has expired, its storage conditions also need to be considered.

Summarize

To determine whether PET thermosensitive silver paper has expired, it can be done from multiple aspects such as observing the appearance of the paper, using fire baking method for detection, identifying through natural light irradiation, inspecting packaging and labels, and considering storage conditions. If the color of the paper is too pale, the surface color is uneven, it turns brown after being baked, it quickly turns black under natural light, or the storage conditions are poor and it has exceeded its shelf life, it may mean that the paper has expired or the quality is poor. When purchasing and using PET thermosensitive silver paper, it is recommended to choose products from legitimate channels and well-known brands, and follow the correct storage and usage methods.