Many people encounter an annoying problem when using laminating film to seal documents, photos, or certificates: cracks appear along the edges or surface shortly after sealing. So why does laminating film crack? Today, we'll briefly analyze the causes and teach you how to avoid it.
1. Laminating temperature is too high
Laminating film uses heat to melt the adhesive layer, firmly bonding it to the paper. If the machine temperature is set too high, the surface of the film will become brittle and prone to cracking after cooling.
Solution: Refer to the recommended temperature for the laminating film, generally between 90°C and 130°C, and adjust according to the thickness of the film.
2. Laminating temperature is too low
If the temperature is too low, the adhesive layer will not fully melt, resulting in a weak seal. Once the film cools, it will crack with even the slightest flex.
Solution: Increase the temperature appropriately based on the thickness of the laminating film to allow the adhesive layer to fully fuse.
3. Using an inappropriate thickness
Using a film that is too thin to seal very hard cardboard, or a film that is too thick to seal very soft paper, thermal expansion and contraction can easily cause stress, leading to cracking.
Solution: Choose a laminating film that is appropriate for the paper thickness and intended use, such as common 80-, 100-, or 125-mic laminating films.
4. Laminating film quality issues
Poor-quality laminating film has a poor bond between the base material and the adhesive layer, resulting in poor toughness and rapid cracking after sealing.
Solution: Choose a manufacturer with a quality assurance system and test samples before wholesale purchases.
5. Improper cooling after laminating
The film is still hot after sealing. Immediately bending or applying heavy pressure can cause cracks on the surface.
Solution: Allow the sealed document to cool naturally on a flat surface before proceeding.