What are the effects of long-term exposure to sunlight on self-adhesive coated paper?

Long-term exposure to the sun, self-adhesive coated paper will be affected by many aspects, these effects mainly from the sun in the ultraviolet, infrared and other invisible light damage to the paper and printing ink. Specifically, the impact includes the following aspects:

1. Fade

Reason: The ultraviolet light in the sun will make the printing ink on the self-adhesive coated paper poor light resistance, resulting in the ink losing the original bright color, the color gradually lightened and even became gray. In particular, when light color inks and four-color plates are overprinted, yellow and red colors fade faster, while cyan and black fade relatively slowly.

Impact: The appearance of the label becomes dim, affecting the beauty and recognition, which is particularly unfavorable for application scenarios that need to maintain the color brightness for a long time (such as outdoor advertising, commodity packaging, etc.).

2. Texture changes

Reason: sunlight will cause damage to the fiber structure and surface coating of self-adhesive coated paper, evaporation of water inside the paper, resulting in paper dehydration, loss of due moisture content, damage to the water balance of the paper, and then make the texture of the paper hard or brittle.

Impact: The mechanical strength of the paper is reduced, and it is easy to be damaged in the process of transportation, handling, etc., affecting the integrity and use effect of the label.

3. Printing ink stability problem

Reason: Long-term exposure to the sun will make the printing ink fade, fall or chemical reactions. These changes not only affect the visual appearance of the label, but may also have an impact on the safety of the items to which the label is attached, such as food packaging.

Impact: The printing quality is reduced, the label information may be blurred, or even fall off, and can not meet the basic requirements of identification and warning. For application scenarios such as food packaging, it may also pose a threat to food safety.

4. The sealing performance is reduced

Reason: Under high temperature sun irradiation, the sealing performance of self-adhesive coated paper may be affected, resulting in damage or opening in the package.

Impact: affect the preservation effect and safety of food, shorten the shelf life of products.

5. Less viscosity

Reason: sunlight and high temperature may cause the glue properties on the self-adhesive coated paper to change, and the viscosity is weakened.

Impact: Labels are easy to fall off and cannot meet long-term fixed requirements.

Coping measures

In order to reduce the adverse effects of solar exposure on self-adhesive coated paper, the following measures can be taken:

Choose a self-adhesive coated paper material with excellent quality and good light resistance: ensure that the label can maintain a good appearance and performance when exposed to the sun for a long time.

Avoid direct exposure to sunlight: try to store the label away from direct sunlight or protect the label with an occlude such as a hood.

Control the storage environment: Keep the storage environment dry and cool to avoid damage to labels caused by humidity and high temperature.

Regular inspection and maintenance: For labels that need to be used for a long time, their status should be checked regularly, and problems such as fading and deformation should be replaced or repaired in time.