Traditional metalization, even with plasma treatment, can result in poor metal to polymer substrate bonding. This produces de-lamination, which leads to packaging failure and results in rejected work.
Part of the problem is low surface energy on the metal side, which also contributes to poor lamination bonding. There is increasing demand in the industry for higher levels of metal adhesion on metalized film due to the need for more complex packaging structures, which requires a lamination peel strength suitable for functional needs.
To address this common issue in the packaging industry through its vacuum metalizers, Bobst is eliminating the need for chemically treated films.
High bonding strength is achieved on any substrate with the Bobst AluBond metallizing process. This is an advanced metal adhesion technology where metal adhesion values can be achieved of up to 5N/15mm.
The Bobst AluBond process is an inline hybrid coating technology that promotes chemical anchoring (chelation) of the first aluminum particles, creating a metalizing seeding layer that provides superior bond strength properties.
Very high adhesion is achieved when there are direct chemical bonds between the aluminum coating and the polymer surface.
Bobst AluBond has been shown to increase metal bond strength and metal adhesion on most commonly used substrates (PET, BOPP, CPP and PE) during aluminum vacuum metalization.
In addition, Bobst AluBond has also been shown to increase dyne level retention, which translates in improved ink wettability during printing and enhances structure stability during lamination. Bobst AluBond generates added value by extending surface energy stability on metalized films over a long period of time and may eliminate the need for an additional surface treatment boost like corona refresh prior to converting.