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How does Cold Seal Packaging Work?  Frequently Asked Questions about Cold Seal 

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Granola Bars

Choosing a sealant for your packaging and need to know if cold seal is right for you? Our frequently asked questions come from customers just like you who are curious about cold seal technology and want to determine if it’s the right application for them. 

As more than a manufacturer but a partner, Sonoco understands that every detail of your packaging matters. These answers to popular questions are meant to guide you so you can make confident, informed decisions in the best interest of your brand, your product, and your customer. 

What is Cold Seal?

Cold seal is a water-based cohesive coating used to seal a variety of paper and film packaging materials. Cold seal is a self-seal adhesive only requiring pressure to seal. As the name implies, cold seal does not require heat. 

Think peeling open a candy bar or nutritional bar and seeing a bit of adhesive residue. That residue in the seal area is likely cold seal (or cohesive) coating.  

What Markets and Products are Best for Cold Seal? 

• Baked Goods 
• Candy Bars 
• Cereal Bars, Nutritional Bars, and Protein Bars 
• Confection  
• Frozen Ice Cream  
• Specialty Snacks

Why Use Cold Seal? 

• Airtight Seals  
• Back Side Printing Option for Promotions  
• Broad Coat Weight Range 
• Fast Line Speeds  
• Fast Ramp Up and Ramp Down Times 
• FDA Compliant for Direct Food Contact  
• Limited Product Damage  
• Low Odor and No Flavor Impact  
• Safety Features  
• Simplified Maintenance 

Why Use Cold Seal instead of Heat Seal? 

• Better registration control on packaging machines than when using heat seal.  
• Less product damage than when using heat seal.  
• Less streaking and ghosting than when using heat seal.  
• Maintenance Improvements:  Compared to heat seal, cold seal results in fewer leakers and a projected increase in the lifespan of cutting knives and seal jaws since they are not heated. The simpler and quicker startup of cold seal also results in reduced waste.  
• Safety: Fewer safety concerns since manufacturers are not working with the heated seal jaw used for heat seal.  
• Speed: Cold seal will double the line speeds of traditional heat seal process. Customers can also expect a 30%-50% increase in line speeds compared to low temperature sealing films. 

Download the Cold Seal vs Heat Seal Comparison Chart

How Easy is it to Convert from Heat Seal to Cold Seal? 

Typically, it is not very difficult to transition from heat seal to cold seal. Most Horizontal Form Fill and Seal packaging equipment that runs heat seal flow wrap can run cold seal flow wrap. Some customers may only need to turn off the heated seal jaws to start running cold seal. For customers who want specific results with the end seals, the customer may need to purchase a seal jaw designed for cold seal. 

The exact steps necessary to transition to cold seal depend on your equipment and packaging needs. Sonoco has helped both large and small consumer packaged goods companies transition from heat seal to cold seal. Contact us at Flexibles@Sonoco.com to let us help you determine your next course of action for the transition. 

What Printing Options are Available with Cold Seal? 

• Rotogravure  
• Flexography  
• Advanced Flexography 

Sonoco has the capability to run cold seal with each of these printing types. 

What about Cost? 

Exact costs depend on your packaging details and current equipment. Sonoco offers competitive pricing, and many of our customers tell us this competitive pricing is one of the reasons why they chose Sonoco as a supplier. Please contact Flexibles@Sonoco.com to tell us about your specific packaging needs and to get a more specific cost estimate.  

Why Choose Sonoco? 

Whether you are new to cold seal or are just looking for a new supplier, Sonoco has resources and expertise at every phase of the process. Sonoco is not just a manufacturer; we are a partner. Sonoco can provide customers with expertise to supply a structure that meets packaging and barrier requirements, design and insights support through The HiveSM Design Services, technical support to fulfill production, and an assigned salesperson to be a consistent point of contact. Our end-to-end solutions can make transitions to new structures or new suppliers as seamless as possible and the final solution as excellent as possible. 

Why do Our Customers Say They Choose Sonoco? 

• Competitive Pricing 
• In-house Insights and Design Services  
• Shipping Costs and Timing 
• Superior Quality Assurance 
• Variety of Printing Options

How do I Get in Touch to Learn More about Cold Seal? 

Contact us at Flexibles@Sonoco.com. Tell us more about your product and packaging, and we can provide specific answers to your unique needs. Check out Sonoco Flexible Packaging if you would like to learn more about our offerings.