Flexible Packaging Materials Archives - Greener Corporation

Seal Integrity Objectives and Obstacles to Achieving Them on Flow Wrappers and Vertical FFS Baggers

Michael Wojtech — Mon, 30 Mar 2026 13:27:38 +0000

A Tech Bite from Greener Packaging Technology Engineer Steve Tucker

How do you define a successful seal on packages from your flow wrappers or vertical baggers? What obstacles can prevent you from achieving these standards?

This Greener Tech Bite helps you evaluate your seal integrity objectives and explores the limitations of your flexible packaging material and production output requirements that can prevent you from achieving these objectives.

Seal Integrity Objectives

Each product has different needs for barrier protection from oxygen, moisture, and/or light, and has different shelf life requirements. These criteria dictate both the structure of the flexible material the product is packaged in and the levels of seal strength and hermiticity that are required.

It’s important to clearly understand the protection requirements of your product.

For nonperishable products that only need a dust cover or containment, such as plastic cutlery, there’s no need to spend money or waste time and effort attempting to achieve hermetic seals. But for some baked goods and other products that need more protection to extend their shelf life, maintaining a quality seal with the properly specified packaging material is vital. Most packaging applications fall somewhere between these two extremes and require some careful consideration.

If you can’t clearly state the reasons for your current seal integrity requirements, it’s a good idea to reevaluate your criteria—you could be wasting money on overly stringent goals or be losing market share by sending out packages that don’t keep your product fresh.

Flexible Packaging Material

Once you are satisfied that your seal integrity objectives address the protection needs for your product, you can re-examine your flexible packaging material choice to make sure the structure can achieve these standards..

Requirements for puncture resistance, tear resistance, and for specific graphics, colors, and glossiness also much be considered.

Production Output Goals

The production output goals you have for your flow wrappers or vertical baggers will also influence the packaging material structure that you need.

On heat seal applications, sealing jaw temperatures typically cycle up and down as they transfer heat to the package and then recover.

Maximum production speeds are limited by the need to maintain these temperature cycles within the seal range of the packaging material—the span between the seal initiation temperature and distortion temperature. The seal range narrows as machine speed increases and dwell time is reduced.

Flexible packaging materials with limited seal ranges may be utilized to reduce costs or to achieve sustainability goals.

Improvements to sealing jaw design and machine setup can reduce temperature cycles and broaden the seal range to help you achieve success with these materials.

But a seal range that is too narrow can reduce machine speed and prevent you from reaching your production output requirements.

Conversely, an overqualified material with a wider-than-required seal range adds unnecessary expense to your operation.

Your packaging material should meet, but not exceed, your requirements for product protection, machinability, and production output levels.

Seal Integrity Testing

Your method for testing seal strength and hermeticity levels of packages should align with, but not exceed, your seal integrity objectives.

For a product that simply needs a dust cover, any testing more elaborate than a simple hand squeeze test might be a waste of time and effort. But a product that requires a moisture and oxygen barrier to stay fresh necessitates a more reliable, accurate test such as Pressure Decay or Gas Flow Detection.

If you’d like guidance with evaluating your seal integrity objectives, specifying and trialing packaging materials, seal testing, and setting up your flow wrappers and vertical baggers for success, consult with Greener’s Technical Specialists.

We provide integrated parts and technical service solutions worldwide.

The post Seal Integrity Objectives and Obstacles to Achieving Them on Flow Wrappers and Vertical FFS Baggers appeared first on Greener Corporation.

Why Trials of New Flexible Packaging Materials Fail When They Don’t Need To

Michael Wojtech — Sun, 21 Sep 2025 13:41:42 +0000

A Tech Bite from Greener Vice-President & co-owner Matt Wojtech

The failed trial of a new flexible packaging material may have more to do with the trial process than the structure of the material.

Problems often occur when new materials are trialed on machines that retain adjustments and components designed for the previous material. This is especially true for new sustainable structures, with increased heat sensitivity and narrower seal ranges that often require specialized sealing jaws and optimized machine setup to run properly.

This Greener Tech Bite compares two different trial processes for flexible packaging materials on flow wrappers and vertical baggers that often yield contrasting results.

The Circular Trial Process

Packagers, material suppliers, and converters often get caught in the following Circular Trial Process:

New Flexible Packaging Material Specified

A material supplier or converter works with the packager to specify a material that will help them reach their corporate goals and provides material for a trial.

Factory Trial with Current Sealing Jaws & Minor Adjustments

The packager trials the new material in one of their factories, utilizing existing sealing jaws and only making minor adjustments to their flow wrapper or vertical bagger.

Factory Trial Fails

The trial is unsuccessful. They are unable to meet seal integrity and/or machine speed requirements, and the new material is deemed a failure.

Modified Version of New Material Specified

The packager’s process returns to stage 1, and the material supplier or converter provides a modified version of the new material.

Factory Trial with Modified Material

A second factory trial is run with the modified material, again using the existing sealing jaws.

Factory Trial with Modified Material Fails

Results improve slightly, but seal quality fails to meet quality standards at the machine speeds necessary to meet production requirements.

Circular Trial Process Repeats

The process again repeats, and may do so multiple times before a successful trial occurs or the project reaches an impasse.

The cost is high not just monetarily, but also for the long time it takes to develop and approve a new material. When forced to rely on this Circular Trial Process, packagers often don’t meet their goals in the desired timeframe or are forced to settle for substandard package quality and/or productivity.

The Expedited Trial Process

With Greener’s Expedited Trial Process, we partner with packagers, material suppliers, converters, and OEMs to prevent the repetitive efforts and failed results of the typical Circular Trial Process and reduce the time required to move from project inception to successful trials.

Through our Expedited Trial Process:

New Flexible Packaging Material Specified

The packager works with the material supplier or converter, often with input from Greener, to specify a material that will help them reach their corporate goals.

Partnering with Greener Corporation

The packager and/or the material supplier or converter partner with Greener Corporation for the trial process. They send us rolls of the new material.

Trial of New Material in Greener’s Packaging Lab

Greener trials the new material in our Packaging Lab on a horizontal flow wrapper or vertical bagger. The optimal sealing jaw design and machine setup for the new material are determined and utilized for the trial.

Packages are tested to ensure they meet the packager’s quality standards. Testing methods include the Vacuum Decay Test for seal integrity, the Seal Strength/Burst Resistance Test, and Microscopic Evaluation.

A Seal Range Graph is created to determine optimal temperatures and machine speeds for the material. Seal Range can be used to identify potential modifications to the structure that could increase productivity or reduce material costs.

Using optimized sealing jaws and machine adjustments, the trial succeeds.

Recommendations are provided for sealing jaw designs and setup specifications for the packager’s flow wrappers or vertical baggers.

Factory Trial with Recommended Jaw Design & Setup

A factory trial utilizing the new sealing jaw and setup recommendations is run with the new material.

A Greener Technical Specialist attends the trial to help optimize packaging machine setup and ensure that factory trial results match those achieved in our Packaging Lab.

Factory Trial Succeeds

The factory trial produces successful results.

Greener’s Expedited Trial Process for Flexible Packaging Materials reduces costs by shortening the new material development process and by allowing packagers to maintain seal integrity standards and production levels.

Trials of new flexible packaging material often fail when they don’t need to.

If you are a packager, material supplier, or converter and want to improve your trial process to get faster, more accurate results, contact Greener Corporation. We provide integrated parts and technical service solutions worldwide.

The post Why Trials of New Flexible Packaging Materials Fail When They Don’t Need To appeared first on Greener Corporation.

How the Structure of Flexible Packaging Materials Impacts Their Sealability

Michael Wojtech — Wed, 23 Jul 2025 16:10:26 +0000

A Tech Bite from Greener Packaging Technology Engineer Steve Tucker

This Greener Tech Bite explains how the structure of a flexible packaging material effects its seal range and ultimately determines maximum machine speeds.

We examine legacy technologies as well as today’s sustainable materials, and discuss how Greener’s new sealing jaw technology expands the seal range to increase production speeds and improve package quality on flow wrappers and vertical FFS baggers.

In previous Tech Bites, we’ve defined seal range as the difference between the seal initiation temperature and seal distortion temperature during the packaging process. We’ve shown that the seal range must be wide enough to accommodate the normal temperature cycles of the sealing jaws.

Flexible Packaging Materials

Polymer Type & Thickness

To explain the impact of flexible packaging material structure on seal range, we will focus on the type and thickness of both the core layer polymers and the sealant layer.

Laboratory Melt Point Spread

One of the more important polymer attributes is the melt point of the core layers, which varies significantly between polymer types. The higher the melt-point, the more resistant the material becomes to heat-related damage at high temperatures.

The sealant layer is designed to have a lower melt temperature than the core layers.

We can refer to the spread between the sealant layer melt point and the core layer melt point as the laboratory melt point spread, which relates only to theoretical temperatures, without respect to the packaging conditions required for the material to reach those temperatures.

Seal Range

Melt Point Spread is not quite the same as seal range, which is a bit more complex. Rather than looking solely at a material’s theoretical melt points, seal range describes the machine settings necessary to achieve those melt points.

A true seal range study will describe the relationship between sealing jaw temperature, dwell time, and force, and will ultimately determine the optimized settings necessary to maintain seal quality.

Laboratory Melt Point Spread vs Seal Range

The seal initiation temperatures and distortion temperatures of a material’s seal range are always higher than the laboratory melt points. The difference is a function of a material’s thermal conductivity and thickness, along with the available dwell time and force.

Thermal Transfer Efficiency (TTE)

During the sealing process, temperatures are highest where the sealing jaws contact the package and then dissipate as heat travels through the core layers to the sealant. This heat transfer becomes a race against time.

The goal is to optimize Thermal Transfer Efficiency (TTE)—to reach seal initiation temperature at the sealant layer as quickly as possible, without heating the core layers to their distortion temperature.

Force, and the efficient distribution of that force, is the key driver of Thermal Transfer Efficiency.

Seal Range Factors

Dwell Time – Machine Speed

As machine speed increases and dwell time is reduced, the seal range narrows.

Flexible Packaging Material Thickness

Increasing a material’s thickness also narrows the seal range; the core layer distortion-point is raised, but the seal initiation temperature is raised even higher.

Temperature

Temperatures can be increased, but machine speed is limited by the need to keep normal sealing jaw temperature cycles within the seal range.

Flexible Packaging Material Structure

Compared to many other materials, polyester offers a broader seal range that enables excellent seal integrity even at high machine speeds.

Materials with a narrower seal range, including many sustainable structures, have often required slower machine speeds to maintain seal quality.

Increase Thermal Transfer Efficiency (TTE) to Expand Seal Range

Significant increases to the Thermal Transfer Efficiency of the sealing jaws can mitigate machine speed limitations. As Thermal Transfer Efficiency is improved, optimum heat will be transferred from the sealing jaws into the packaging material at a lower temperatures and/or in less time, allowing for a wider seal range that provides increased machine speed.

XR™* Sealing Jaws

Greener Corporation’s XR™* Sealing Jaws, utilizing unique serration geometry and Dura-Therm material, provide this increased Thermal Transfer Efficiency by distributing a machine’s existing sealing force more effectively.

Sustainable Materials & Difficult to Seal Packages

XR™* Sealing Jaws provide the broader seal range that can be especially critical with sustainable materials and difficult to seal packages, where the need for longer dwell times has previously created package quality and machine speed limitations.

Reduce Flexible Packaging Material Costs

Increased Thermal Transfer Efficiency can also maintain seal quality and machine speeds with thinner or less expensive sealant layers that reduce flexible packaging material costs.

Are you missing opportunities to expand your seal range to increase machine speed, improve seal quality, and reduce costs?

Contact Greener Corporation’s Technical Specialists. We provide integrated parts and technical service solutions worldwide.

The post How the Structure of Flexible Packaging Materials Impacts Their Sealability appeared first on Greener Corporation.

Use Sealing Jaw Carbon Impressions for Preventative Maintenance

Michael Wojtech — Tue, 29 Apr 2025 07:47:34 +0000

A Tech Bite from Greener Technical Service Specialist Chris Stawasz

Sealing jaw carbon impressions are a vital diagnostic tool for solving cutting and sealing problems on flow wrappers and vertical baggers, and they also play a vital role in preventative maintenance.

This Greener Tech Bite outlines five opportunities where sealing jaw carbon impressions help you prevent problems from occurring in the first place.

Take Sealing Jaw Carbon Impressions

Whether solving problems or preventing them, always label your impression with the date, line and machine, direction arrow, and sealing jaw pair number so you can compare results over time and track changes.

We use “carbon impression” as a general term, but in practice make sure you use the correct paper for your application.

Carbon paper works best with unheated rotary sealing jaws and with reciprocating jaws at lower temperatures.

Use carbonless paper, also known as NCR paper, with heated rotary jaws and with reciprocating jaws at higher temperatures.

1. When You Install New Sealing Jaws

When you install new sealing jaws, bring them to operating temperature and use carbon impressions to evaluate your setup.

Clearance

For rotary jaws, use carbon impressions to ensure that the clearance between the upper and lower shafts is properly set and parallel.

Phasing

A carbon impression will also indicate if the phasing between the shafts is synchronized.

Alignment

For both rotary and reciprocating jaws, carbon impressions indicate if the serrations are misaligned.

Pressure

And carbon impressions will help you adjust sealing pressure so that it is even from side to side and across the length of the jaws.

2. Before You Install New Knives and Anvils

When knives and anvils on flow wrappers need to be replaced, remove the worn parts, make sure jaw temperatures are set correctly, and take a carbon impression before you install new knives and anvils. This quick, easy test will indicate if readjustments are needed to restore your standard setup and prevent future problems.

3. After You Clean the Sealing Jaws

A pause in production for cleaning provides another opportunity. After you clean the jaws, check your temperature settings and run a carbon impression to determine if spring pressure, alignment, or other settings have changed and need to be readjusted.

4. When You Run New Flexible Packaging Materials

Carbon impressions also provide vital feedback when you test and run new flexible packaging materials. Before you run a new material, bring your sealing jaws to operating temperature and run a carbon impression to ensure that your adjustments are at standard levels.

Take additional impressions as you test the new material; your new structure may have a different heat seal range, thickness, stiffness, or other characteristics that require refinements to your sealing jaw and knife setup.

5. Every Week and During Downtime

Systematic carbon impressions provide the feedback you need to prevent packaging problems. Schedule weekly carbon impressions from each flow wrapper and vertical bagger, and take additional impressions when opportunities arise during product changeovers and other downtime.

If you’d like help diagnosing your carbon impressions, send us a photo at custserv@greenercorp.com. We’ll help you identify adjustments that improve packaging performance.

Greener Corporation provides integrated parts and technical service solutions worldwide.

The post Use Sealing Jaw Carbon Impressions for Preventative Maintenance appeared first on Greener Corporation.

XR™* Sealing Jaws Improve Thermal Transfer Efficiency to Provide Better Seals, Faster

Michael Wojtech — Fri, 29 Nov 2024 19:15:52 +0000

What if a new, unique design for sealing jaws could provide better seals, faster than you thought were possible on vertical baggers and long dwell flow wrappers?

This Tech Bite explains how Greener Corporation’s XR™* Sealing Jaws dramatically improve Thermal Transfer Efficiency to:

Improve Package Quality
Increase Machine Speed
Run Sustainable Materials & Hard to Seal Packages
Reduce Flexible Packaging Costs

The Sealing Process

Seal Range and Temperature Cycles

The seal range for your packaging material and conditions spans between the seal initiation temperature and the distortion temperature. The seal range must allow for sealing jaw temperature cycles as the jaws transfer heat to the package and then recover, and for wider temperature cycles when production slows down or is interrupted.

Machine Speed

The effective seal range narrows as machine speed is increased and dwell time is reduced. Machine speed is limited by the need to keep normal temperature cycles within the effective seal range.

Thermal Transfer Efficiency

During the sealing process, Thermal Transfer Efficiency determines the dwell time required to transfer heat from the sealing jaws to the sealant layers of the packaging material.

Force

Increasing the force that closes the sealing jaws improves Thermal Transfer Efficiency by increasing the surface contact between jaws and the packaging material.

But the ability to increase force is limited on most vertical baggers and long-dwell wrappers.

XR™* Sealing Jaws

1. Improve Package Quality

Utilizing unique serration geometry and Dura-Therm material, Greener Corporation’s XR™* Sealing Jaws distribute a machine’s existing sealing force more effectively to increase Thermal Transfer Efficiency and improve package quality.

2. Increase Machine Speed

The improved Thermal Transfer Efficiency yields wider seal ranges at shorter dwell times to allow increased machine speeds.

3. Run Sustainable Materials & Hard to Seal Packages

XR™* Sealing Jaws increase seal quality and machine speed where the need for longer dwell times has previously created limitations, such as with thicker and stiffer materials, wider packages, gusseted applications, mono PE and other materials with narrow seal ranges, and poorly conducting materials like paper.

4. Reduce Flexible Packaging Costs

By increasing Thermal Transfer Efficiency, XR™* Sealing Jaws enable users to decrease sealant thickness or utilize less expensive sealants with higher seal initiation temperatures to reduce flexible packaging material costs without sacrificing seal quality or productivity.

To learn how XR™* Sealing Jaws can:

Improve Package Seal Quality
Increase Machine Speeds
Run Sustainable Materials and Hard to Seal Packages
Reduce Material Costs

on your vertical baggers and long dwell flow wrappers, contact Greener Corporation. We provide integrated parts and technical services worldwide.

* patent pending

The post XR™* Sealing Jaws Improve Thermal Transfer Efficiency to Provide Better Seals, Faster appeared first on Greener Corporation.

Flexible Packaging Materials Consulting

Michael Wojtech — Mon, 23 Sep 2024 17:10:52 +0000

Greener Corporation provides a broad range of Flexible Packaging Materials Consulting resources for flow wrappers and vertical baggers.

Whether you need to assess your current material or evaluate new structures, our materials and machinery experts can help you Establish Objectives, Identify Options, Run Trials, and to Select and Implement the material that best meets your objectives.

Integrated Solutions

Greener’s integrated approach considers how the design and condition of your flow wrappers or vertical baggers will affect results and determines what machine adjustments or component updates may be needed.

Early Involvement & Collaboration

The earlier in your selection project that we work with you, and the more we collaborate with packagers, machinery OEMs, and materials suppliers, the more effectively we can integrate four essential elements of your process to produce optimal, timely results.

1. Establish Packaging Objectives

Greener can help you establish clear packaging objectives, based on the requirements of your product, distribution channel, and other criteria, that provide important standards for evaluating a material’s performance.

Barrier Properties

Barrier Properties protect against the transfer of odors, gases, or moisture.

Seal Integrity

Seal Integrity should correlate with your barrier requirements.

Sustainability

Sustainable recyclable and compostable materials must meet specific compositional and structural guidelines.

Machinability

Machinability testing indicates how a material’s thickness, stiffness, coefficient of friction, thermal conductivity, and other properties affect the packaging process.

Cost

Per-package material cost and the anticipated costs of machine downtime and scrap rates must also be considered.

2. Identify New Material Options

If you are unable to meet your objectives with your current material, we can help determine a list of new material options—perhaps even suggesting materials you may not have considered.

3. Trials and Evaluations

To help narrow your initial list down to the most promising options, Greener can assist with preliminary machine trials at your facility or run these trials in our Packaging Lab.

We can then help you run more extensive trials with this refined list of materials.

Adjustments and Part Designs

Before you run trials, Greener can assess the characteristics of these materials and recommend machine adjustments or updates to former, sealing jaw, and other part designs that are needed to optimize results and get a truer picture of each material’s potential.

A new material that meets your objectives for sustainability, for instance, might require higher seal initiation temperatures and be more easily damaged by excess pressure.

Package Testing

To evaluate machine trial results, we’ll help you establish criteria and determine the best package testing methods. For example, if your product does not require a material with a strong oxygen barrier, then seal integrity does not need to be hermetic.

Packages can be tested at your facility or in our Packaging Lab.

4. Select and Implement New Material

Well executed machine trials and testing can be used to determine which flexible packaging material best meets your objectives in a production setting.

We will help you implement changes to adjustment procedures and component designs, along with any necessary training, on the wrappers or baggers that will run the new material and ensure consistent results across different makes or models of machinery and at multiple facilities.

Greener’s Flexible Packaging Materials Consulting provides an additional resource to help you integrate and improve all aspects of your packaging process.

To learn more about solutions for improving package quality and productivity on flow wrappers and vertical baggers, contact Greener Corporation. We provide integrated parts and technical services worldwide.

The post Flexible Packaging Materials Consulting appeared first on Greener Corporation.

Sustainable Packaging 3: Running Paper-Based Materials on Flow Wrappers and Vertical FFS Baggers

Michael Wojtech — Mon, 26 Aug 2024 11:28:21 +0000

Paper-based flexible packaging is increasingly considered as a sustainable alternative to polymer-based flexible packaging solutions.

Segment 3 in Greener’s Sustainability Series explores potential obstacles to forming and sealing paper-based materials on flow wrappers and vertical baggers and presents solutions for maintaining package quality and productivity with these new structures.

Paper-Based Flexible Packaging Materials

Characteristics

Four characteristics of paper affect its performance.

1. Sealability

First, paper is not sealable by itself. To be utilized in flexible packaging, paper must also include a cold seal adhesive or heat activated sealant layer.

Paper is also less thermally conductive than most polymer-based materials which may led to sealing problems.

2. Barrier

Paper alone does not provide adequate barrier protection and requires additional treatments to contain the product’s aroma and flavor and protect against outside contaminates.

3. Recyclability

To be considered recyclable, paper-based flexible packaging must contain at least 70-90% paper, depending on regional or national requirements.

This criterion limits the thickness of additional sealant and barrier layers and can affect their functionality.

4. Thickness and Stiffness

Paper-based materials also tend to be thicker and stiffer than traditional materials, with significantly less capacity for elongation.

Forming Issues

The characteristics of paper-based flexible packaging materials can make forming more difficult.

These thicker, stiffer materials require extra tension to draw them through the wrapper or bagger and can be easily buckled, wrinkled, and damaged by standard forming components, causing sealing problems and fractures to sealant and barrier coatings that leave them less effective.

These forming issues may not be readily apparent, so packages should be regularly tested.

Forming Solutions

Specialized Formers

Specialized formers designed for paper-based flexible packaging are often required to maintain even, consistent tracking that alleviates excess stress and damage.

Greener Corporation partners with Kenray Forming to provide these specialized forming solutions.

Power Film Drive

Wrappers and baggers without a power film drive may need this feature added, since relying exclusively on fin wheels or belts can magnify forming problems with paper-based materials.

Fin Wheels

On flow wrappers, customized fin wheel designs such as gripper grooves and Dura-Therm material may be needed to draw the thicker and stiffer material and prevent slippage.

Sealing Issues

Heat Sealing Problem

As explained in our previous Tech Bite, the effective seal range of a packaging material is defined as the difference between the seal initiation temperature and the distortion temperature.

With all materials, machine speeds are limited by the need to fit normal sealing jaw temperature cycles within the seal range.

Paper-based structures, with greater thickness, stiffness, lower thermal conductivity, and potentially thinner sealant layers, can require longer dwell times for heat from the sealing jaws to reach and activate the sealant. This reduces their seal range and may lead to sealing problems.

Reductions to machine speed may be necessary to seal the package and caulk off leaks.

Pressure

The heat transfer limitations of paper-based materials, along with their extra thickness and stiffness, can make it difficult to apply the sealing pressure required to produce quality seals—especially across gaps at the corners and at the fin or lap seal.

Sealing jaw setup and design become especially critical. The serrations must apply enough pressure to activate and help move the limited amounts of sealant into gaps to caulk off leaks, yet not exert excess pressure that crushes or splits these more easily damaged structures.

Sealing Solutions

Setup and Adjustments

Adjustments that work with traditional materials may need to be checked with carbon impressions and refined for greater accuracy.

Dura-Therm Sealing Jaws

Sealing Jaws made from Greener’s proprietary Dura-Therm alloy provide more responsive and consistent thermal conductivity to reduce temperature cycle fluctuations, helping to keep them within the paper-based material’s seal range and to maintain production speeds.

Sealing Jaw Serration Pattern

To provide the even, consistent heat transfer and sealing pressure that paper-based structures require, your sealing jaw serration pattern should be custom designed for your specific material, machinery, and conditions.

Easy Seal™️ FLEX Jaws

And Greener’s Easy Seal™️ FLEX Jaws further optimize sealing pressure by compensating for the extra layers of material at the fin seal.

Collaboration

Collaboration is a key component for successfully running paper-based flexible packaging materials.

Greener Corporation works with packagers, machine manufacturers, and material suppliers to provide material evaluations, setup and procedural changes, customized components, and technical service solutions.

Paper-based flexible packaging materials have been most widely implemented on cold seal applications for products with less stringent barrier requirements, such as some candy, and on secondary packaging for multi-packs of previously packaged items.

The ultimate goal is to enable the use of these and other sustainable materials for a wider variety of applications without sacrificing seal quality or productivity.

To learn more about running sustainable materials on flow wrappers and vertical baggers, contact Greener Corporation. We provide integrated parts and technical services worldwide.

The post Sustainable Packaging 3: Running Paper-Based Materials on Flow Wrappers and Vertical FFS Baggers appeared first on Greener Corporation.

Forming Packages on Flow Wrappers: Problems and Solutions

Michael Wojtech — Mon, 05 Aug 2024 14:30:19 +0000

Package formation is the foundation for producing quality packaging on flow wrappers; it affects everything from package appearance and seal quality to scrap rates and downtime.

This Greener Tech Bite presents methods to improve the forming process on flow wrappers that optimize package quality, save time, and decrease packaging material costs.

Forming Packages on Flow Wrappers

Formers are not standard components—their design and precision have a big impact that often goes unrecognized.

As the former shapes the packaging material into a tube around the product, it must create even contact and tension with the material to accurately maintain tube size and proper tracking as the fin wheels pull the tube forward and seal the longitudinal fin seal.

Forming Problems

Excessive or inadequate contact and tension between the former and the packaging material at any point in the forming process creates four types of packaging problems:

1. Scored, Creased Packages

Score marks or creases make packages visually unappealing, and this damage can reduce the material’s barrier properties.

2. Wrinkles and Pleats

Wrinkles and pleats make it difficult to seal off leaks at the intersection of these additional cross-sectional layers while avoiding excess pressure that crushes or splits the seal.

3. Fin Seal Issues

Poorly performing formers can cause the fin seals to be uneven, and create loosely wrapped packages with narrow fin seals that pull free from the fin wheels and halt production while the material is reset.

4. Torn, Broken Packaging Material

Inadequately performing formers can also tear or break the packaging material and require time-consuming re-threading.

Forming Solutions: Kenray Horizontal Forming Tool

Kenray Forming, a packaging problem solutions partner with Greener Corporation, has developed a new Horizontal Forming Tool that mitigates these four forming problems and provides additional benefits.

With their innovative design and consistent high precision, these formers maintain even contact with the packaging material to provide more consistent tracking and help you:

Minimize the Occurrence of Scored, Creased Packages

Eliminate Wrinkles and Pleats that can Cause Seal Problems

Solve Fin Seal Issues That Delay Production

Prevent Torn, Broken Flexible Packaging Material

Run Traditional and New Sustainable Packaging Materials

Kenray’s Horizontal Forming Tool solves forming problems with new sustainable films and paper-based packaging materials that prevent them from running properly with standard formers.

Make Fewer Adjustments and Reduce Downtime

The Horizontal Forming Tool optimizes performance with a wider range of flexible packaging materials and conditions to reduce downtime due to machine adjustments to solve forming problems or during changeovers.

Maintain Precise Angle of Entry

Kenray’s former also solves problems by incorporating the the final unwind roller into the former.

The roller position is pre-set for your packaging conditions, so the material consistently enters the former at the correct angle. Adjustment variations that cause poor performance are eliminated.

Reduce Fin Seal Width to Decrease Material Costs

With standard formers the fin seals on packages are typically designed wider than is required for seal integrity, to prevent the fin from pulling free from the fin wheels when typical tracking variations occur.

Kenray’s new Horizontal Forming Tool mitigates these tracking variations, so fin seal widths can be reduced to decrease per package material costs while maintaining quality and avoiding production delays.

An integrated approach to optimizing package quality and productivity on flow wrappers begins with package formation.

To learn how optimally designed and adjusted formers, knives, and sealing jaws can improve your packaging results, contact Greener Corporation and Kenray Forming. We provide package quality and productivity solutions worldwide.

The post Forming Packages on Flow Wrappers: Problems and Solutions appeared first on Greener Corporation.

Review of Seven Seal Testing Methods for Flexible Packaging

Michael Wojtech — Tue, 28 May 2024 17:59:22 +0000

Before you can determine the best seal testing method for your flexible packaging application, you need to clearly identify your requirements for seal strength and hermiticity. Then you can use these criteria to evaluate different methods and to accurately interpret test results.

This Greener Tech Bite explains the objectives, methods, results, and limitations of seven common seal tests for packages produced by flow wrappers and vertical baggers. We begin with seal strength tests, followed by tests for hermeticity, and conclude with a summary chart for easy comparison.

1. Peel Strength Test

Objectives: Peel Strength Tests measure seal strength, the ability of a package to remain sealed when subject to tension.

Methods: Seals are produced on a lab sealer at a series of different temperatures, with pressure and dwell time remaining constant. A testing device measures the force required to peal each seal apart.

Results: The force required to peel a unit width of seal is correlated with sealing temperature to compare the seal strength of one packaging material against another, or against historical data.

Limitations: Set points for temperature, pressure, and dwell time are typically standardized to ensure repeatability and inter-lab correlatability. They don’t necessarily represent production settings and therefore don’t indicate real-world results.

Sometimes seals are tested by pulling them apart by hand. This method does not produce repeatable Peel Strength results, though a seal that fully delaminates across the package width indicates seal strength that exceeds the material’s tear resistance.

2. Hot Tack Test

Objectives: Hot Tack Tests measure the strength of a seal while still warm.

Methods, Results, & Limitations: Test methods, results, and limitations are very similar to peel strength tests, except force is applied instantaneously, before the seal can cool.

3. Burst Resistance Test

Objectives: Burst Resistance Tests measure the pressure required to burst a package.

Methods: An unrestrained package is inflated until the internal pressure causes seal failure.

Results: Burst pressure values are often used to evaluate the effects of elevational pressure changes when packages are shipped.

Limitations: Since outcomes depend on package size and geometry—a given pressure level generates greater force across a wider package—Burst Resistance Tests don’t provide easily comparable values for seal strength.

4. Water Vacuum (Bubble) Test

Objectives: The Water Vacuum Test identifies the presence and location of leaks and is also used to assess leaks caused by pressure changes during shipping.

Methods: Packages are held under water in a sealed tank, where a vacuum is drawn. Bubbles appear when air inside the package is forced through leaks from higher to lower pressure.

Packages may also be squeezed under water by hand to look for bubbles.

Results: The presence of bubbles provides visible evidence of leaks and their location.

Limitations: Water Vacuum Tests don’t accurately measure leak size, since results are influenced by the initial air fill, size, and geometry of the package. Initial air fill must also be considered when assessing the impact of pressure changes during shipment.

Since the manual squeeze test is not accurately repeatable, results can be inconsistent.

5. Dye Leak Test

Objectives: Dye leak tests can also indicate the presence and location of leaks.

Methods: Colored dye is injected into the package, which is held for a set time with the seal oriented horizontally at the bottom and then inspected.

Results: Leaks are indicated by places where the dye has migrated through the seal.

Limitations: The Dye Leak Test tends to be less sensitive for smaller leaks and doesn’t quantify the magnitude of leaks.

6. Pressure Decay Test

Objectives: Pressure Decay tests measure both the presence and the magnitude of leaks.

Methods: A package is inserted into chamber, where a vacuum is drawn that pressurizes the package. If leaks are present, air is forced from the package into the chamber and the vacuum pressure decays.

Older pressure decay methods don’t use a chamber or create a vacuum, but instead inject air to achieve pressurization.

Results: Reductions in pressure indicate leaks; the rate of reduction reflects the size and overall magnitude of the leaks.

Limitations: With older Pressure Decay testing devices, the pressurized package will expand in volume. Excessive pressurization may result in seal creep or stretching and skew results. This limits the maximum seal test pressure, especially as package size increases.

The newest devices resolve these issues by restraining the package in a flexible bladder that prevents the pressurized package from expanding, allowing much higher pressures to be used.

Since the natural pressure decay rate decreases as pressure decreases, as illustrated on this graph, results from this test method are more precise for smaller leaks and lose accuracy as leak sizes increase.

7. Gas Flow Detection Test

Objectives: Gas Flow Detection Tests also measure the presence and magnitude of leaks.

Methods: A package is inflated or evacuated with a needle probe; the device monitors the gas flow required to maintain a set pressure level.

Results: Any gas flow required to maintain a given pressure indicates the presence and magnitude of leaks.

Limitations: Since pressure levels produced by Gas Flow Detection devices are limited, accuracy is best for medium to larger sized leaks.

Summary Chart: Seven Seal Testing Methods for Flexible Packaging

This summary chart will help you compare all seven seal tests for flexible packaging on your flow wrappers and vertical FFS baggers.

If you’d like help defining your sealing objectives and evaluating seal testing methods, contact Greener Corporation. We provide package quality and productivity solutions worldwide.

The post Review of Seven Seal Testing Methods for Flexible Packaging appeared first on Greener Corporation.

Sustainable Packaging Materials 2: Running Mono Polyethylene & Mono Polypropylene on Flow Wrappers & Vertical FFS Baggers

Michael Wojtech — Thu, 08 Feb 2024 14:51:49 +0000

Most traditional flexible packaging is made from multiple layers of different materials that can’t be easily separated. Mono polyethylene (PE) and mono polypropylene (PP) are produced from the same or similar materials, and are the most common polymer-based sustainable packaging materials we’ve encountered so far.

Segment 2 in our Sustainability Series explores the properties that can make mono PE and mono PP more challenging to form, cut, and seal, and presents solutions for maintaining package quality and machine speeds when running these materials on flow wrappers and vertical FFS baggers.

FORMING Mono PE & Mono PP Packaging Materials

During the forming process, the thicker, stiffer nature of mono PE and mono PP structures creates greater tension in the web. On both flow wrappers and vertical baggers, a power film drive will help keep these structures tracking properly.

Specially designed formers are often required to maintain consistently sized packages that are free from creasing and scoring.

CUTTING Mono PE & Mono PP Packaging Materials

The mechanical properties of these thicker and stiffer structures can also make cutting more challenging.

Knives designed for your specific packaging material will improve cutting performance.

Special features such as an extreme angle zig zag knife can improve openability for the consumer.

SEALING Mono PE & Mono PP Packaging Materials

As explained in our previous Tech Bite, the effective seal range of a packaging material is defined as the difference between the seal initiation temperature and the distortion temperature.

With all flexible packaging materials, machine speeds are limited by the need to fit normal sealing jaw temperature cycles within the seal range.

Many current mono PE and mono PP structures have a lower distortion temperature, which decreases their seal range.

And since these mono structures tend to be thicker and stiffer, higher sealing jaw temperatures are needed for heat to reach and activate the sealant layer. This further reduces the seal range.

With sealing jaw temperature increases limited by the lower distortion point, reductions to machine speed may be necessary to provide adequate dwell time for seal initiation.

Sealing Solutions

Advanced sealing jaw designs can help mitigate sealing issues encountered with mono PE and mono PP materials. Sealing jaws made from Greener Corp’s proprietary Dura-Therm alloy provide more responsive and consistent thermal conductivity across the sealing face to reduce temperature cycle fluctuations and help maintain seal quality and machine speeds.

Temperatures don’t spike as high when the machine idles, or drop as far when the line restarts.

Customized sealing jaw serration patterns and options such as Easy Seal™ FLEX jaws can also reduce temperature cycles by optimizing thermal transfer and sealing pressure.

In addition to sealing jaw design, optimized adjustment procedures and training are critically important for maintaining seal quality and machine speeds on flow wrappers and vertical baggers.

To learn more about sustainable flexible packaging materials, advanced part designs, machine adjustments, and training, contact Greener Corporation.

We provide integrated parts, industrial packaging solutions and technical services worldwide.

The post Sustainable Packaging Materials 2: Running Mono Polyethylene & Mono Polypropylene on Flow Wrappers & Vertical FFS Baggers appeared first on Greener Corporation.