BOBST announces breakthrough in high metal adhesion


K5 EXPERT from BOBST with vacuum metallization technology (photo: BOBST)
K5 EXPERT from BOBST with vacuum metallization technology (photo: BOBST)

The AluBond process developed by the Bobst Group (Lausanne, Switzerland) is reported to provide high metal adhesion and surface energy levels through vacuum metallization. Traditional metallization, 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 product rejects and loss of reputation. 

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 metallized film due to the need for more complex packaging structures which requires lamination peel strength suitable for functional needs.

BOBST has developed an innovative approach to address this common issue in the packaging industry through its vacuum metallizers, eliminating the need for chemically treated films. High bonding strength is said to be 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 in-line hybrid coating technology which promotes chemical anchoring (chelation) of the first aluminium particles creating a metallizing seeding layer that provides superior bond strength properties. Very high adhesion is achieved when there are direct chemical bonds beteen the aluminium coating and the polymer surface. Increased chemical bonding by the creation of the seeding layer increases lamination bond strength and leads to high performance during lamination, extrusion and coating processes hence preventing failure of the packaging.