Metal Closures

Closing the Gap between Glass and Plastic

Finding An Ideal Solution in Closures
By Joseph Pierce, President, CROWN Closures Americas

Today, many large retailers are requiring beverage and food producers to transition to plastic to reduce breakage and shipping weight as well as satisfy consumer demand.  Making a transition while maintaining brand integrity and product quality is, on multiple levels, a significant packaging challenge.   For example, transferring a long established, well-recognized glass package that consumers know and trust to a plastic container can create branding issues in the marketplace.   In addition, products that require high heat processing, such as retort and hot fill packaging, face technical hurdles during the transition. 

A composite closure – a two-piece cap comprised of a central metal disk and plastic outer ring – can help brands make the transition from glass to plastic by bridging a gap in both the way consumers perceive brands on the store shelf as well as how the product is actually processed.    Composite closures also offer the opportunity to enhance food or beverage packages with more usability and better visual appeal.  The results can mean the difference between a material compromise and an entirely new brand look that borrows from the past and looks to the future.



Maintaining Premium Look

While cost is a consideration when it comes to packaging, established brands often do not compete on price but on brand loyalty and familiarity.  Products from orange juice to pickles often use packaging as a first step of differentiation.  Using plastics that are shaped similarly to glass containers is a first step.  Although most metal closures do not work with plastic jars and bottles, hybrid or composite closures can be used on plastic.  A composite closure on a plastic container helps retain the traditional look of a package but adds a new twist.   Even the “pop” associated with metallic closures, while technically a safety feature, is a sound that consumers associate with product integrity.

Usability and Safety

Consumers associate metals with premium quality, but at the same time appreciate convenience.  A composite closure offers the best of both worlds with a metallic upper surface that is secured by a plastic ring.   The ring is easier to open but also serves as an important safety feature.

Safety with composite caps is two-fold.  The first layer is in the metal disk that maintains an airtight seal against the container.  That seal can only be broken by twisting the outer plastic ring, which lifts the metal disk.  The plastic ring provides a second level of protection with a tamper-evident drop-down section which separates before the metal disk seal is broken.  This level of tamper evidence also eliminates the need for a foil inner seal and the associated secondary line operation, which may cut packaging costs and improve overall line efficiencies.     Choices in containers and container finishes will impact the amount of torque needed to break the seal.  This allows brand managers and packagers the ability to balance safety and convenience. 

With composite closures, brands also retain the familiar and reassuring “pop” when the consumers open the package.  This “pop” is simply an enhancement to the closure’s tamper evidency.  It also has an emotional connection with consumers that immediately speaks to the product’s freshness.

Branding Space

Most brands that have used glass packaging with metal closures already know the value of branding on the closure itself.  This is an important interface between consumers and brands as they use the product day to day.  A composite closure allows for full branding on the metallic portion, giving consumers a familiar brand interface that can be vital to consumer loyalty.  In addition, decorated metal conveys a premium look and feel that has long been associated with familiar brands.

A Heated Issue

For many products, transitioning to plastic can mean overcoming the pasteurization and/or retort requirements of processing.  Plastic closures cannot withstand the rigors of the retort process.  Composite closures are suitable for pasteurization and retort and can be an important part of successfully transitioning from glass to plastic or plastic to glass, if desirable.  As examples, Crown Holdings now provides its IDEAL™ composite closure to Libby’s for use on pasteurized plastic jars of premium fruit.  Crown also provides a smaller diameter retortable composite closure to Ross Products for that company’s popular Ensure® nutritional drink, now promoted for its convenient reclosability.  Successful conversions have also taken place with tomato sauces, jellies and jams, orange juice, baby formula, and applesauce.

Summary

Successfully transitioning from glass to plastic involves a wide range of strategies from container shaping to new processing techniques.  Closures are an important part of this conversion, helping to convey a premium brand image to consumers, enhance usability and aid in many of the processing hurdles of the transition.  Incorporating closures early in the package redesign process can ensure that consumers are drawn in by a traditional value-added look and find that product usability has actually been enhanced.

About Crown Holdings, Inc.
Crown Holdings, Inc., through its subsidiaries, is a leading supplier of packaging products to consumer marketing companies around the world. World headquarters are located in Philadelphia, Pennsylvania.

For more information, contact:

In the United States: Terry Zeik, VP, Sales, CROWN Closures Americas; Tel: 740-681-6521; Email: .

In Europe: Thierry Lainez, Marketing & Communications Manager, CROWN Closures Europe; Tel: +33 1 49 18 40 45; Email: .