The reason why PP self-adhesive bags are so transparent and bright is mainly determined by the following factors:
1. The characteristics of the material itself (polypropylene)
PP (polypropylene) has a high degree of crystallinity, neat molecular arrangement, good light penetration, and thus high natural transparency.
Compared with PE (polyethylene), PP has a more regular molecular chain, a lower refractive index, and less haze, so it looks clearer and brighter.
2. Use BOPP film (biaxially oriented polypropylene)
The self-adhesive bag commonly uses BOPP film (Biaxially Oriented Polypropylene Film), which is a PP film that has been biaxially stretched.
This stretching process can improve the flatness, tensile strength and surface finish of the film, making the bag look smoother, brighter and more textured.
3. High surface smoothness and good reflection
The surface of BOPP film is very flat and smooth, and it can evenly reflect light when it is irradiated, thus showing a "mirror feel", which makes the bag very bright.
4. Moderate thickness, enhanced transparency
The thickness of BOPP film generally used for self-adhesive bags is about 20~40 microns, which is not too thick to affect softness, but transparent enough to present a "clear and transparent" visually.
5. Suitable for printing and gluing
PP material is suitable for combination with self-adhesive, sealing stickers, and printing inks. The appearance will not turn white or foggy. The overall finished bag is clean, beautiful, and bright.
6. Summary of application advantages:
Features Advantages
High transparency Good display product effect
High gloss Improve packaging grade and visual appeal
Material is crisp Not easy to deform, and the packaging effect is clean and neat
Water-resistant and oil-resistant Suitable for stationery, accessories, clothing and other industries
PP/BOPP self-adhesive bags are a high-end transparent packaging bag with great cost-effectiveness, especially suitable for industries that need to display the appearance of goods, such as clothing tags, accessories, postcards, manuals, electronic product accessories, etc.
