Bostik’s wide range of cold seal adhesive coatings combine natural rubber latex (NRL) with proprietary synthetic polymers for high-performance sealing. Available in formulations for mono-web and laminate structures, these solutions offer balanced cohesion and adhesion, delivering more dependable seal integrity and consistent sealability than competitive options.
Take a look at some key advantages, applications, tips and more!
Ready to get started with our cold seal adhesive coatings?
Contact a Bostik expert today!
Cold Seal Adhesive Coating Tips & More
for Food & Other Packaging Applications
Increased energy savings
Improved Sustainability
Enhanced Reliability
IncreaseD Energy Savings
Improved sustainability
Enhanced reliability
Key Advantages
• No additional heat required to form a package
• Minimal dwell and pressure needed
• Fast packaging line speeds
• Adhesion to bio-based, paper and film materials such as OPP, PE and PET
• Suitable for compostable substrates when compostable formula is used
• Approved for How2Recycle pre-qualification letter for PE film store drop-off recycling
• Reduced risk of material distortion due to no excess heat needed to bond
• Formulated with anti-block systems to give low cling, consistent sealability and freshness
TREND ALERT: Surface Print
Recently, the market has been shifting away from laminating toward surface print where feasible. A primary driver of this shift is sustainability—a way to use less material. This is because surface print requires just one film, while laminated uses two or more films together.
HOW BOSTIK HELPS YOU ADDRESS IT
HOW BOSTIK HELPS YOU ADDRESS IT
Bostik’s cold seal and overprint varnishes portfolios support the transition to a single ply structure. Additionally, Bostik’s cold seal is certified for the How2Recycle Store Drop-Off program for monolayer or laminated PE structures.
When used in cold seal adhesives, NRL facilitates fast line speeds. However, care must be taken in processing, as NRL is susceptible to shear thickening. This means that under stress or shear, its viscosity will increase, shifting from a liquid to a semi-solid state. Thickening can impede converting by making the adhesive difficult to process and should be avoided.
WORKING WITH NATURAL RUBBER LATEX (NRL)
Aqueous Cold Seal
Converted Cold Seal
Packaged Product
• Keep above 40°F/4°C
• Discard if frozen
or coagulated
(Warming will not return the adhesive to a usable state.)
• Store converted rolls above 25% relative humidity, regardless of temperature
• Rehumidify before use if exposed to a relative humidity at or below 25% for prolonged periods*
• Warehouse at any temperature from freezer to elevated heat, regardless of humidity conditions
*If stored at or below 25% relative humidity for prolonged periods, performance may be impacted.
Storage conditions for cold seal adhesives depend on the process stage and state.
STORAGE TIPS
Bostik recommends taking the following steps when using adhesives made with NRL:
NRL PROCESSING TIPS
Tubing
Pumps
Doctor Blade
Downtime
Mixing
Laminated
• Nutritional
• Confectionary
• Bakery
• Protective Films
• Mailers
• Collecting Cards
Surface Print
• Miniature candy
• Frozen single serve
• Protective Films
• Sterilization Packaging
• Dishwasher Tablets
• Hotel Toiletries
Overwrap
• Individually-wrapped candy
• Cheese slices
• Medical Overwrap
Key APplications
Tubing
Avoid NRL-based tubing and components in your cold seal application system as it can promote thickening (due to the tendency of NRL to adhere to itself)
Mixing
Reduce splashing by using low mixing speeds and flexible splash guards so that splash will not dry and attract additional, wet cold seal causing it to congeal and impede processing
DownTime
Lift the blade and flood the cylinder if downtime is 10+ minutes, in order to avoid applying unnecessary shear
Doctor Blade
Increase angle to 70° or above as decreasing the surface area of interaction between the cold seal and doctor blade will decrease the shear forces
Pumps
Use low-shear pumps to reduce stress on the adhesive and minimize the chance of thickening
Legal Disclaimer