Tag Archives: food packaging
Manufacturers often encounter a similar puzzle, when cleaning invisible contaminants from a surface, how do you know when the surface is clean; how clean is clean enough? This is a common question that manufacturers ask when preparing their surfaces for bonding, coating, sealing, printing or painting. Until now, there hasn’t been an objective and reliable way to answer this question. Successfully cleaning a surface directly correlates to the adhesive ability of the surface. In order to get something to stick reliably the surface must be clean. How we define that parameter is different for a variety of materials.
For example, you clean your car differently than you clean your dishes. Why? Because a car rides on the road through rain, smog, dirt, maybe mud, and the other is a vehicle for your food.
At BTG Labs, our answer to the “clean enough” question is, “Depends on what you’re doing.” There are dozens of critical surface preparation processes that exist for a number of different applications. A handful include:
- Flame treatment on polypropylene bumpers prior to painting
- Plasma treatment on PET catheters prior to coating
- Hand sanding and solvent wiping on aircraft nut plates before adhesively bonding to composite
- Grit-blasting titanium golf clubs in preparation of bonding to composite
- Corona treatment on film for packaging prior to metallization, lamination, or coating
Food packaging and print industries often face the obstacle of adhering to low energy substrates such as polypropylene. Measuring the surface’s cleanliness prior to bonding or printing is the key to successful adhesion. The common method for measuring surface cleanliness, or surface energy on these materials is dyne inks. However, dyne is highly subjective and requires a skilled technician, and because of its destructive nature, dyne can only be used on a sample rather than an actual material on the assembly line. These downfalls often restrict the use of dyne inks.
This paper examines the relationship between surface energy and adhesion and how water contact angle provides an accurate and quantitative method for predicting adhesion. The results of this paper reveal that the Surface Analyst, a handheld water contact angle measurement instrument is an accurate and effective indicator of surface energy. …Read More