What is OPP protective film
The OPP protective film is a plastic film made of OPP as a substrate, single-sidedly coated with acrylic glue and laminated with a release film (single layer does not conform to the release film). The OPP plastic film has a smooth and transparent surface and high temperature resistance. Good weather resistance.
According to electrostatic adsorption, medium viscosity, high viscosity, high tensile strength, light weight, non-toxic, odorless, environmental protection, a wide range of applications, adhesion, high viscosity, OPP protective film product portfolio is usually a bottom layer, release type Paper, release film.
Why there is adhesive residue
After the OPP protective film is used, after the protective surface protective film of the article is peeled off, residual pressure sensitive adhesive is found on the protected surface and cannot be easily removed. It has to be said that this is the most troublesome for manufacturers and manufacturers of protective films. Residual glue problem.
It not only destroys the beauty of the object, but also causes the pollution of the material being protected. Why does the surface protective film appear to be sticky?
There are usually three cases of adhesive residue:
First, cohesive destruction: Pressure sensitive adhesive on both the surface to be protected and the substrate, and the protective film coating surface loses luster.
Second, the destruction of the sticky base: the protected surface has more rubber residue, the protective film coating surface visible substrate.
Third, migration residue: There is a small amount of pressure-sensitive adhesive residue on the surface to be protected, and the protective film coating surface luster is kept well.
The reason for the occurrence of adhesive residue is more complicated. Different substrates cause the above-mentioned three kinds of residual adhesive. One of the more common reasons is that the peel strength of the protective film has changed after a period of time, after the protective material is pasted on the protective film. It will take a while to get it off.
Short only a few minutes, but long in more than 1 year, most of them in 3-12 months, during this time, the peeling strength of the protective film tends to increase with the extension of time, usually after the first fast Slow, and finally stabilized. When the peel strength rises to exceed the cohesive strength or the tack force, cohesive failure or damage to the tacking agent occurs, resulting in a residue.
Another reason is the aging of the OPP protective film. The protective film consists of a plastic substrate and a pressure-sensitive adhesive. Both of them are high-molecular polymers. The main aging mechanisms include heat aging and ultraviolet light aging. After aging of the protective film, the macromolecular chains constituting the substrate and the pressure-sensitive adhesive are broken, the average molecular mass is reduced, the cohesive strength is reduced, and the cohesive failure occurs.
Compatibility with the surface material of the item to be protected is also an important factor in causing residue. According to the principle of similar compatibility, compatibility between substances with similar structures and properties is likely to occur.
Over time, pressure-sensitive adhesive and the surface to be protected due to compatibility, the two gradually merge, causing increased peel strength, resulting in cohesive failure or damage to the adhesive base; or part of the small molecules in the pressure-sensitive adhesive layer The substance is compatible with the surface to be protected, thereby migrating from the pressure sensitive adhesive to the protected surface, causing migration residues.