01
Start with the job of the bond
Lamination combines film layers so the finished structure can perform functions that must remain connected through printing, converting, filling, distribution, storage, and use.
Film layers
Identify the exact substrates, gauges, surface treatments, coatings, metallization, foil, paper, or sealant films being joined.
Required function
Define whether the bond supports protected print, barrier, stiffness, toughness, opacity, heat resistance, sealing, forming, or another requirement.
End-use exposure
Record product chemistry, fill and process temperature, moisture, oils, acids, sterilization or retort conditions, distribution, storage, and expected use.
Approval evidence
Establish the bond, appearance, migration or regulatory, package-integrity, machinability, and product-compatibility evidence the application requires.
02
Know which processes are being compared
| Method | How the film layers are combined | Primary process question |
|---|---|---|
| Solvent-based adhesive lamination | An adhesive carried in an organic solvent is coated, the solvent is removed in a drying system, and the film layers are laminated and cured. | Can the adhesive, drying, solvent-control, cure, and finished structure meet the end-use requirement? |
| Water-based adhesive lamination | An adhesive carried or dispersed in water is coated, the water is removed, and the film layers are laminated. Cure requirements depend on the system. | Can the substrates, treatment, dryer capacity, bond development, and end use support the selected water-based system? |
| Solventless adhesive lamination | Metered reactive components are mixed and applied without an organic-solvent or water carrier, then the film layers are laminated and the adhesive develops properties during cure without a carrier-drying step. | Can mixing, metering, coating, cure, migration control, and release timing be managed for the application? |
| Thermal lamination | A prepared laminate or sealant film has a heat-activated resin or adhesive layer that bonds to a printed web as the films pass through a heated nip. | Are the printed web, ink, thermal film, activation conditions, and finished-package requirements qualified as one system? |
| Extrusion lamination | A thin layer of melted resin is extruded between two webs and becomes the bonding or tie layer as the structure is pressed and cooled. | Are the webs, resin, treatment or primer, heat, coat weight, web handling, and production economics appropriate? |
03
Solvent-based adhesive lamination
In typical solvent-based dry-bond lamination, adhesive is applied to one film and the solvent is evaporated in a drying oven. The second film is then laminated to the coated film, and the completed structure is allowed to cure before further converting or use.
Solvent-based adhesives are often considered for demanding applications involving heat, aggressive product ingredients, chemical exposure, foil, or thermal processing. The specific adhesive, films, curing conditions, and completed structure must still be qualified for the application.
Solvent-based lamination requires sufficient drying capacity and careful control of coating weight, line speed, temperature, airflow, and solvent removal. The converter must also manage emissions, flammability, worker safety, energy use, residual solvent or odor, and the time required for the adhesive to cure before the laminate is released. These are process requirements and tradeoffs, not indications that solvent-based lamination is inherently problematic.
Potential advantages
Solvent-based systems offer a broad range of adhesive chemistries and have a long history across film, metallized film, and foil structures. Depending on the specific formulation, they can provide strong wetting, bond development, heat resistance, and resistance to demanding product ingredients or processing conditions.
Questions and limitations
Confirm the converter's solvent-handling and drying capability, process controls, residual-solvent requirements, cure and release schedule, and whether the selected adhesive is approved for the actual product and process.
Application examples
Solvent-based lamination may be considered for retort, hot-fill, boil-in-bag, vacuum packaging, foil laminations, and packages containing oils, acids, fragrances, chemicals, or other ingredients that can challenge the adhesive. The adhesive and complete structure must be specifically rated and validated for the actual product and process.
04
Water-based adhesive lamination
In typical water-based dry-bond lamination, an adhesive carried or dispersed in water is applied to one film. The water is removed in a drying oven before the second film is laminated to it. Cure or bond-development time depends on the particular adhesive system.
Although the carrier is water, it still must be fully removed from the coated film. Dryer capacity, temperature, airflow, coating weight, and line speed can affect drying and bond development. The converter must also control surface treatment, wetting, foam, and the possibility of trapping moisture within the finished structure.
Potential advantages
Water-based adhesives can reduce the use of organic solvents and associated VOC emissions. Depending on the formulation, they can provide good clarity and reliable bonding to properly treated films, including PE, PP, PET, nylon, and some metallized structures.
Questions and limitations
Confirm dryer capability, surface treatment, wetting, foam control, coating weight, line speed, cure or bond-development time, moisture-sensitive film layers, and the performance range of the specific adhesive.
Application examples
Water-based lamination is commonly considered for general and medium-performance applications such as snacks, dry foods, powders, labels, and selected transparent or metallized film structures. More demanding heat, chemical, moisture, or product-exposure requirements must be evaluated against the capabilities of the specific adhesive.
05
Solventless adhesive lamination
Solventless lamination commonly uses two reactive adhesive components that are precisely mixed, metered, and applied without a water or solvent carrier. The films are laminated without a carrier-drying oven, and the adhesive develops its final properties as it cures.
Solventless lamination requires close control of the mixing ratio, adhesive temperature, viscosity, metering, coating weight, nip conditions, and film treatment. Initial bond strength may be limited before cure, so curing time can affect when the laminate is ready for slitting, pouch making, shipment, or product contact.
A solventless adhesive should not be assumed suitable for hot fill, boil-in-bag, retort, or chemically aggressive products simply because it is solventless. The specific adhesive and completed structure must be designed and qualified for the intended exposure, and the required cure and food-contact or migration conditions must be met before use.
Potential advantages
Because there is no water or solvent carrier to remove, solventless lamination can reduce drying energy, eliminate solvent emissions from the adhesive carrier, and use a more compact laminating process. It can also support efficient production at relatively low adhesive coating weights.
Questions and limitations
Confirm mixing and metering accuracy, operating window, initial bond, cure and release time, migration requirements, surface treatment, and compatibility with the complete structure and production schedule.
Application examples
Solventless lamination is widely used for film-to-film and film-to-metallized-film structures in applications such as snacks, confectionery, bakery products, frozen foods, meat and cheese packaging, and other general barrier packages. Specifically rated systems can also serve more demanding hot-fill, boil-in-bag, chemical-resistant, or retort applications.
06
Thermal lamination
Thermal lamination is commonly used with digitally printed flexible packaging. A specially prepared laminate or sealant film has a heat-activated resin or adhesive layer. The prepared film and printed web pass through a heated nip, which activates the layer and forms an immediate bond between the films.
Qualified thermal-lamination systems create usable bond strength immediately, eliminating the adhesive cure period before slitting or pouch making. This can shorten total lead time, simplify production, and make the process especially useful for digitally printed short runs, multiple SKUs, launches, and fast-turn packaging programs.
The printed web, ink system, heat-activated film, temperature, nip pressure, line speed, and cooling must work together as a qualified system. A thermal film should not be assumed compatible with every digital print process or package application, and the completed structure still needs to meet the required bond, barrier, sealing, product-contact, and end-use performance.
Potential advantages
Qualified systems provide immediate bond strength without an adhesive cure period, which can simplify production and support the shorter runs, multiple SKUs, and faster turns associated with digital printing.
Questions and limitations
Thermal lamination requires specially prepared and compatible films, which can cost more than standard films used with conventional adhesive lamination. Available structures, barriers, sealants, suppliers, and application ranges may also be more limited, increasing the finished-package cost even when the process improves speed.
Application examples
Depending on the qualified film system, applications can include stand-up pouches, three-side-seal pouches, sachets, stick packs, pillow bags, flow-wrap packaging, and other digitally printed roll-stock or premade-pouch structures.
07
Extrusion lamination
In extrusion lamination, a thin layer of melted resin is extruded between two moving webs. The layers are pressed together and cooled, allowing the resin to bond the webs while also becoming a functional layer within the finished structure. Extrusion coating is related, but applies melted resin to a substrate without necessarily adding a second web.
Extrusion lamination is especially useful when the bonding layer also needs to contribute to the package. It is commonly used to combine film, paper, paperboard, foil, or nonwovens in applications such as liquid and aseptic packaging, dry-food and powder packaging, pouches, medical packaging, industrial wraps, and reinforced sacks. It may be selected because the extruded resin can bond dissimilar webs while adding functional thickness, moisture resistance, stiffness, toughness, or other resin-dependent properties.
Extrusion lamination requires close control of resin selection, melt temperature, coating weight, surface treatment or primer, web tension, nip pressure, and cooling. Heat-sensitive films, poor resin-to-web compatibility, uneven coating, neck-in at the web edges, and inadequate treatment can affect adhesion or the finished structure. Because the process uses specialized equipment and can require more setup, it is often better suited to applications and volumes that justify the production economics.
Potential advantages
The extruded resin can do more than bond the webs. Depending on the resin and construction, it can also contribute thickness, stiffness, moisture resistance, sealability, opacity, or other functional properties. Extrusion lamination can combine films with materials such as paper, paperboard, foil, or nonwovens.
Questions and limitations
Confirm substrate heat sensitivity, resin-to-web compatibility, surface treatment or primer, melt temperature, coating uniformity, neck-in, web tension, cooling, line configuration, setup, and run-size economics.
Where it fits
Extrusion lamination works well when the construction benefits from a functional extruded layer and the converter's equipment, run size, and production economics support the process.
08
Choose from the application and converter reality
- Define the film layers and the function that lamination must provide.
- Identify product chemistry, filling, sealing, thermal processing, storage, distribution, and regulatory requirements.
- Compare the specific adhesive or resin systems as well as the broad process category.
- Confirm the converter's equipment, controls, qualified substrates, minimums, production speeds, drying or cure capacity, and quality checks.
- Approve the delivered laminate and finished package using testing appropriate to the application's actual risks. This may include bond, appearance, barrier, sealing, migration or regulatory compliance, product compatibility, machinability, and finished-package integrity.
FIELD CHECKLIST
Information to collect
Use this as a working prompt, then adapt the final specification or validation plan to the actual application.
- Exact film layers, gauges, treatments, coatings, metallization, foil, paper, or sealant substrates
- Function required from the bond and from any adhesive, thermal, or extrusion layer
- Product chemistry, fill temperature, heat process, moisture, oils, acids, and other exposures
- Bond strength, appearance, odor, migration, regulatory, and compatibility requirements
- Converter equipment and qualified solvent-based, water-based, solventless, thermal, or extrusion capabilities
- Coating or extrusion weight, line speed, drying, mixing, metering, thermal activation, treatment, and web-handling controls
- Cure, aging, slitting, pouching, shipping, filling, and release schedule
- Finished-laminate and finished-package testing with defined acceptance criteria
- Change-control requirements for adhesive, resin, film layer, treatment, plant, or process changes
COMMON QUESTIONS
Questions worth resolving
Does solvent-based lamination automatically provide the strongest bond?+
No. Solvent-based systems include proven high-performance options, but bond and end-use performance come from the specific adhesive, film layers, surface treatment, coating, drying, cure, and application. The process name alone is not a performance specification.
Where does water-based lamination fit?+
Commercial water-based systems are used for flexible substrates including snack, dry-food, powder, label, transparent, and metallized applications. The selected system must be checked for substrate treatment, dryer capacity, bond development, moisture sensitivity, and the required performance level.
Why is thermal lamination used with digital printing?+
Qualified thermal systems use a prepared film with a heat-activated layer that forms usable bond strength immediately, avoiding an adhesive cure period before slitting or pouch making. The tradeoff is that specialized compatible films can cost more and may offer fewer structure, supplier, and application choices.
Is extrusion lamination the same as adhesive lamination?+
No. Adhesive lamination applies an adhesive between film layers. Extrusion lamination places melted resin between the webs so the resin bonds them and can also contribute thickness or another package function.
REFERENCES & TEST METHODS
Test methods and acceptance criteria should be selected for the actual application. These standards and technical sources support the principles discussed in this guide:
BOBST: Extrusion coating and lamination process and applications↗Bostik: Solvent-based and solvent-free flexible lamination adhesives↗Bostik: PURELAM solvent-free flexible packaging adhesives↗Dow: ROBOND L-168 two-component water-borne laminating adhesive↗Dow: ROBOND L-98D water-borne adhesive for metallized and transparent films↗Henkel: Solventless retort lamination performance and process benefits↗Davis-Standard: Extrusion coating and laminating flexible packaging capabilities↗HP Indigo: Pack Ready thermal lamination process and zero-cure system↗HP and Karlville: Immediate slitting and pouching after thermal lamination↗Nobelus: Heat-activated thermal sealant structure and applications↗