What’s in a Roll Core?

How often have you thought about your material core?

Although it’s vital to roll-to-roll processing projects, the material core often goes unrecognized as a crucial part of the selection process. 

Most products produced at Strouse come in roll form, meaning they’re placed on a liner and wound on a core in the middle of the roll. Today, we’ll explain the roll cores, the types, and other factors in selecting the proper core. 

What Are Material Cores?

A material core is the plastic or cardboard ring used in the center of a roll to support the winding up of die-cut materials. In simple terms, it's what's left over after using all of the tape on a roll.

Types of Roll Cores

Cores come in varieties, and depending on your product needs, Strouse offers different types of cores. Today we’ll cover the difference between plastic and paper cores.

PLASTIC VS. CARDBOARD

PLASTIC CORES

Plastic cores are mostly used for medical projects. They help protect your product from being contaminated by core dust and paper. 

Plastic cores come in five materials: high-impact polystyrene (HIPS), High-Density Polyethylene (HDPE), Polypropylene, PVC, and ABS. 

CARDBOARD CORES / PAPER CORES

Cardboard cores are the industry standard. Because cardboard cores are made from paper products, they can flake and cause tiny dust particles. However, paper cores can be significantly more cost-effective, practical, and environmentally sustainable. 

Paper cores are typically made of heavy-duty, thick cardboard unless they are for toilet paper or paper towels (these cores are made from thinner, less durable cardboard or paper).

Additional Factors 

Aside from the type of roll, there are plenty of other core options from different heights/widths, diameters, options for core labels, and more. Let’s take a closer look.

1. WIDTH

A core's width depends on the product's size. For instance, Strouse custom cuts cores to whatever size the job calls for. We’ve placed die cut parts on cores as small as 0.1875 inches wide.

2. DIAMETER

The diameter of the core is dependent on how the product will be used. Sometimes, the inner diameter is the most important. Other times, it is the outer diameter. 

Your converter may ask questions like, “Will it be placed on a large-scale manufacturing press or a small machine used for automatic placement?” to determine the purpose. 

Most Strouse die cut materials are placed on cores with 3-inch or 6-inch diameters. We also use cores with 1" and 10" diameters, but less frequently. Some of our jobs require custom-sized diameter cores, so ultimately the diameter depends on your application.

3. THICKNESS

The thickness of the cores we use can vary from .02" to .50". Strouse typically uses a set size, but we can always get a custom thickness if required.

4. CORE LABELS

Traceability is essential to many of our customers. Core labels placed on the inside of the core can provide you with lot numbers, the date of manufacture, and the operator number for quality traceability.

5. STROUSE PRINTED VS. NON-PRINTED CORES

The majority of products we manufacture are placed on Strouse printed cores, where the inner paper of the core includes the Strouse logo and brand. 

Occasionally, we manufacture roll goods for a customer who is shipping them off to a separate customer and needs Strouse's name removed from the product. In this case, we will use non-printed cores, where the inner paper of the core is entirely white.

6. ROLL AUTOMATION

Strouse engineers design products to work in conjunction with automated processes. Products are often put on cores to be placed on a machine and easily dispensed. 

Knowing what a product is used for and how it’s applied is essential. Sharing this knowledge with your converter will help determine what type of core your product needs. 

Conclusion 

Finding a suitable material and adhesive with the right roll core is essential to the product design process. 

If you’re interested in sourcing materials for your project design, feel free to reach out and schedule a consultation for additional insight into your planned project.

On the other hand, if you’re curious about roll-to-roll manufacturing, you can check out our Learning Center.

Originally published: January 15, 2014