Archive for the ‘Containerboard’ Category

Searching for Glossary of Industry Terms for US and UK

July 14, 2022

Ted asks:

I’m looking for a glossary of corrugated terms that we use in the United States. Everything to do with corrugated, containerboard, tooling, equipment and testing as much of a comprehensive list as we can compile. We’re working with a company in the UK and their design team is using terms that we’re unfamiliar with or can’t easily translate off the top of our heads. I want to compile a glossary of industry terms with brief definitions, much like a translation lexicon, so they can then add their term next to the relative definition. The goal is to streamline communications and make life easier for both groups.

I have an old Fiber Box Handbook that is the starting point but very incomplete. If you have something that you can send me or guide me to, it would be most appreciated.

Even here in the US we can have different terms for the same thing. Anilox roll and ink roll for example. So, communicating with someone in another country where, for example, ‘printing plates’ may be called ‘stereos’, can certainly be a bit of a task until you learn the lingo.

Below are a few links to some publicly accessible collections of industry terms that are a good source of information and hopefully will contribute to your project.

When you complete your glossary, I hope you will share it with us and our readers.

Glossary of Corrugated Material Terms (Pro Pac)

Packaging Terminology: A glossary of terms and definitions (GWP Group)

The Packaging School Glossary

— Ralph

How Does Pea Starch Compare to Corn Starch

July 6, 2022

Nat asks:

We received an inquiry today from one of our plants about using pea starch as an alternative to corn starch. The question I have is what are the critical properties of unmodified Pea Starch used in corrugating adhesives? Also, is there a Caustic Sensitivity Test Procedure for pea starch.

What a coincidence, just last week we had a presentation by Roman Skuratowskicz from Ingredion regarding this very subject. He has again been so gracious to share his knowledge.

Most of the critical properties are the same that apply to corn starch used in corrugating.

Primarily, the alkali sensitivity must be controlled to prevent the adhesive from having an unstable viscosity and prevent possibility of gelling in storage.

The base starch needs to have consistent viscosity as well. Because of the high variability of base pea material, and the lack of expertise with manufacturing product for corrugating applications, it is difficult to find a consistent source of pea starch for corrugating.

Also, many providers will actually have lower purity (closer to pea flour) since their primary product is the pea protein for food use. This will impact both formulation and stability in storage.

Pea starch is also significantly different than corn starch in formulation. It will require less caustic and borax, is hydrophobic, and has a larger particle size than corn starch which impacts conveyance and cookout. As a result, significant formulation changes will be necessary if you find a consistent source of pea starch. If the starch properties are inconsistent, then each batch will need custom formulation.

We have two internal test methods we use on incoming starch. I’ll provide these as reference only.

    • SMA-A51 – Brookfield UL method – fast test, requires specific instrument.
    • SMA-A52 – settling test method – basic equipment required, takes 24 hours to run and prone to errors, otherwise useful as field test.

Thank you Roman for sharing your knowledge and this useful information.

I’ll research this a bit more as interest in the topic seems to be growing. Some information I have discovered. If, as Roman points out, you can find a supplier with a consistent product, and achieve the proper formulation, tests have shown that pea starch can be stable and have similar performance characteristics to corn starch. The addition of waterproof resins can result in a water resistance exceeding 24 hours.

Tests have shown pea starch has a gel temperature approx. 5 degrees F lower than corn. Therefore, it could lead to lower energy consumption/cost, and faster tack/setup could lead to higher running speeds on the corrugator. However, more research is needed before it’s decided if this is a viable option for NA corrugated operations.

We’ll keep digging, and as usual, if others have knowledge or experience to share, please do.

— Ralph

Outside Air Temp effect on Green Bond

May 23, 2022

Ron asks:

We had an overhead garage door installed prior to our 2018 corrugator project – the OEM had us install it for ease of bringing new equipment into the building. Certain times of the year, say April to October, the corrugator crews have the overhead door open and just have the screen door down to allow fresh outside air in.  This door is maybe 18′ from the corrugator stacker. Should we have any concern about green bond shock on a cooler morning. The stock coming off the hot plate section is 275 degrees +/- and if the outside air temp was 50 would you be concerned about that?  I haven’t been able to find any studies related to this. Your opinion would be greatly appreciated.

I would focus more on the final pin adhesion strength.  You should target values above 45 and up to 60 pounds per foot.  If the pH, viscosity, and starch temperatures in the pan are within your process parameters, green bond should not be an issue.

Let’s toss it out to our readers. Have any of our other corrugator operations had any experience with this scenario?

— Ralph

Linerboard Coefficient of Friction (COF) Target and Max

February 3, 2021

Cassie asks,

I’m doing some investigation to determine what is the minimum, target and maximum COF (coefficient of friction) for linerboard. Can you point me to any information on this?

Instead of answering your question directly from a mill process point of view, which we can do, here are a couple links to several specification sheets from domestic mills. (Domestic High Performance Linerboard, COF Spec Sheets or Slide Angle)

The Europeans do not seem to deliniate slide angle as a physical property characteristic.  Since they have been making linerboard from recovered fibre much longer than we have in the Americas, it may be just universally understood there.

Let me know more if you have more specific questions. I would also recommend membership in TAPPI’s Corrugated Board Technical Committee where you will have access to the best minds in this business.