Water-, Oil- and Grease-Resistance Barrier Coatings for Food Packaging

The purpose of barrier coatings in food packaging is the ability to block water, water vapor and other liquidsfrom passing through materials that typically are highly porous. Not only can these barrier coatings make items like paper and cloth water-resistance, they have the added benefit of blocking grease and oil. At first, that might not sound like a big deal, until you begin to imagine what life might be like without these high-tech barriers, which are actually emulsion polymers.

Stopping by the coffee shop for a morning French Roast, ordering a burger and fries for lunch in a drive-thru, and picking up pizza for dinner are ordinary events that take place millions of times each day across the globe. Each and every time these events happen, consumers intuitively and unknowingly rely on barrier coatings formulated with water-based emulsion polymers to perform without fail. Paper and paper board manufacturers are also depending on a zero fail rate.

That’s because no one wants coffee or any other beverage seeping through a paper cup to stain their clothes and ruin their day. The fast-food lunch and pepperoni pizza, like most food items, contain various amounts of oil and grease, none of which should ever make it onto a car’s upholstery or your favorite jeans. Salads and salad dressings, home-style vegetables, apple pies and chocolate bars present the same types of messy challenges for consumers and food processors.

In order to make food fast and convenient, barrier coatings formulated with styrene-butadiene or styrene-acrylic emulsion polymers are applied to paper and paperboard substrates as thin, lightweight, and translucent coatings. These coatings are often overlooked by the consumer.