To Bubble Free or not to Bubble Free
By Denise Nathan
The latest advance in adhesive technology has been the development of bubble free films. These films have a special adhesive structure with channels that enable air to escape during application. This allows for easy and fast application as the applicator need not be concerned about trapped air bubbles during application or spending time post application piercing air bubbles. These films offer good initial repositionability and wrinkles can easily be pushed out. The end result is a significant reduction in labour time.
When the cost of any job is analysed, the self adhesive vinyl only makes up a small percentage of the overall cost. One of the more significant costs is the labour involved in applying the decal. Any film that is easier to work with and can be applied faster is going to have a substantial impact on labour costs and ultimately increase profitability. While these films are more expensive the overall cost of labour is reduced and productivity is increased so the net result is cost beneficial.
As with any film it is important to be aware of any special considerations or limitations. While the channels allow air to escape, they can also allow water to get in. Water infiltration can seriously compromise the adhesion of the graphic. These films MUST be applied dry. Bubble free adhesives are not suitable for use in applications where there is a lot of exposure to water such as boats and floor graphics. Floor graphics can get exposed to water during cleaning and if the graphics are applied to tiles, water can travel underneath via any grouting and reduce adhesion. Edge sealing the graphics can reduce this problem.
Due to the structure of the adhesive, there are less contact points for the adhesive to make with the substrate. Therefore, the overall adhesion to a substrate can be slightly weaker. This is an important factor in applications where the film is stretched into deep recesses and indentations. A bubble free film has a very high risk of lifting in such instances. For this same reason bubble free adhesives are best suited to larger decals (over 1M2). Smaller graphics mean a smaller surface area to make contact with the substrate and as such small letters will not adhere as well at the initial stages. Also the time saving becomes less significant on small lettering so any benefit in using bubble free is not realised.
When laminating digital prints using a bubble free system it is critical to use the right laminate. Laminates designed for bubble free applications on vehicles are a lot thinner. This is because a thinner, higher quality laminate places less tension on the overall graphic construction so it performs better in more demanding applications.
Whilst properly drying any print is critical to ensure optimal performance it is even more crucial with bubble free products. If the ink is not totally dry the adhesive will be full of solvents which can negatively change the performance of the adhesive. Any benefits in application and repositionability will be negated so the full advantages of a bubble free system will not be realised.
Using bubble free adhesives can bring huge advantages to your business but care must be taken to ensure they are used for the right application and special considerations and processes are observed during printing, lamination and application.
Denise Nathan is Marketing Manager - MACtac in Oceania
denise@mactac.co.nz
www.mactac-europe.com