A Guide to Slitting Techniques: Shear, Crush, Razor, and Score Slitting

Precision slitting is a key step in the converting process for flexible materials. Whether you’re working with films, foams, papers, foils, or pressure‑sensitive adhesive tapes, the slitting method used can directly impact edge quality, tolerances, production speed and overall performance in downstream applications. 

At TPC Converting, we specialize in precision slitting and rewinding services that transform large master rolls into custom widths tailored to your exact application. With more than 55 years of converting experience, our team carefully selects and fine‑tunes slitting techniques based on how each material interacts with blades, equipment, and process parameters. 

Below, we break down the most common converting slitting techniques, including razor slitting, crush cut slitting, shear slitting, and score slitting, and explain when each method is most effective. 

What is Slitting?

Slitting is the process of cutting large rolls of flexible material into narrower rolls or strips that are easier to handle and ready for manufacturing, packaging, or assembly. This process is commonly paired with rewinding, which transfers the slit material onto smaller, more manageable rolls. 

At TPC Converting, our precision slitting and rewinding process typically includes: 

• Unwinding material from a master roll 

• Passing the material through a strategically arranged set of blades 

• Cutting the material to precise, non‑standard widths with tight tolerances 

• Rewinding finished rolls for transport, storage or further converting 

We also offer lathe slitting, which slices a master roll into narrower widths without unwinding. This method is ideal for select applications that require rigid control and minimal material handling. 

Our versatile slitting capabilities support a wide range of materials, including foam, paper, plastic films, foils, and tapes, making slitting a foundational service across many industrial converting operations. 

Different Slitting Techniques 

Choosing the correct slitting method depends on the material type, thickness, desired edge quality, production speed and final application requirements. Below is an overview of the most common slitting techniques used in converting. 

Razor Slitting

Razor slitting uses sharp razor blades to cleanly cut thin, flexible materials. This technique is used for applications where precision, minimal material distortion and clean edges are required.  

Razor slitting is commonly used for: 

• Plastic films 

• Foils 

• Lightweight laminates 

• Fragile or delicate materials 

Because razor slitting creates minimal stress on the material, it is frequently preferred in packaging, electronics, and medical converting applications where edge quality and waste reduction matter most.

Types of Razor Slitting

Razor-in-Air (Top Razor Slitting)

Razor‑in‑air slitting positions the razor blade above the material, cutting it without any additional backing or support beneath the web. Because the blade makes direct contact with the material alone, this method is best suited for slower speed converting operations and applications that require a lighter cutting approach. Razor‑in‑air slitting is a cost-effective option due to its simple tooling, straightforward setup and ease of blade maintenance. It is most commonly used for thin films, foils and other fragile materials to maintain edge integrity while minimizing equipment complexity.  

Razor-in-Groove (Bottom Razor Slitting) 

Razor‑in‑groove slitting cuts the material against a grooved support roll, providing added stability to the razor blade during the cutting process. This additional support allows the material to remain more controlled as it passes through the blade, making the method well suited for higher‑speed production environments and more demanding applications. By stabilizing the web during slitting, the grooved roll helps reduce edge defects and improves overall cut consistency. Razor‑in‑groove slitting is often selected when tighter tolerances, increased throughput and improved edge quality are required. 

Crush Cut Slitting

Crush cut slitting works by pressing a circular knife against a hardened anvil roll, effectively crushing and cutting the material. This technique is often used for softer, compressible materials that respond better to forceful separation. Crush cutting doesn’t dull the blade, which results in much a longer blade life and consistent edges throughout a run.  

Crush cut slitting is ideal for: 

• Rubber materials 

• Foams 

• Certain pressure‑sensitive tapes 

• Other soft or spongy substrates 

While crush cutting is efficient and economical, it may produce a slightly rougher edge compared to shear or razor slitting. For applications where edge appearance is not critical, crush cut slitting offers a simple and effective converting solution. 

Shear Slitting 

Shear slitting uses a male and female circular knife arrangement that creates a scissor‑like cutting action. This method delivers exceptional edge quality while supporting high‑speed production. 

Shear slitting is well suited for: 

• Paper and paperboard 

• Laminates 

• Plastic films and foils 

• Textiles and specialty materials 

Because shear slitting balances speed with precision, it is often selected for demanding applications requiring tight tolerances and superior edge finishes. 

Score Slitting

Score slitting creates a controlled indentation or score line using a blunt blade or scoring wheel. Instead of cutting fully through the material, this method weakens specific areas to allow for precise folding. 

Score slitting is commonly used in: 

• Corrugated sheets 

• Cartons and boxes 

• Folding packaging components 

This technique supports consistent folds and clean bends during packaging production. 

How TPC Converting Delivers Precision Slitting Solutions 

At TPC Converting, no two slitting jobs are treated the same. Our experienced team fine‑tunes each setup based on material behavior, performance requirements and downstream needs. 

With capabilities that include precision slitting and rewinding, cutting, spooling, adhesive laminating and coating, printing, and finishing, we provide custom converting solutions across a wide range of industries. 

Our ISO 9001:2015 and IATF certifications reflect our ongoing commitment to quality, consistency, and customer satisfaction. 

Partner with TPC Converting for Precision Slitting Services 

Whether your application requires razor slitting for delicate films or shear slitting for high‑volume production, TPC Converting has the expertise and equipment to deliver reliable results. 

To learn more about our precision slitting services or explore our full range of converting capabilities, contact us today or visit our converting services page. 

What Is Corona Treatment and How Does It Improve Adhesion in Converting?

Corona treatment is a high‑frequency surface treatment process used in converting to increase surface energy and improve adhesion of inks, coatings and adhesives on low‑energy materials such as rubbers and foams. By modifying only the outermost surface of a substrate, corona treatment enables stronger, more consistent bonding without altering material performance.

At TPC Converting, we provide high frequency, wide‑web corona treatment converting services; a capability offered by only a small number of converters in the United States.

How Corona Treatment Works

Rather than focusing on the basic definition, it’s more helpful to understand what corona treatment actually does at the material level and why it is so effective in converting applications.

Corona treatment works by using high‑frequency electrical energy to modify only the outermost surface of a substrate. This controlled energy alters the surface chemistry by creating additional active bonding sites, allowing inks, coatings, and adhesives to interact more effectively with the material.

Importantly, corona treatment:

• Affects only the surface
• Does not change thickness, strength, or flexibility
• Prepares the material specifically for downstream converting processes

The result is a surface that is more receptive to bonding, enabling stronger adhesion, more consistent print quality, and improved overall product performance, especially on materials that are otherwise difficult to bond.

Why Surface Energy Matters in Adhesion and Converting

Surface energy directly impacts how well a material bonds to inks or adhesives.

Low Surface Energy Materials

• Liquids bead up instead of spreading
• Adhesives struggle to wet-out on the surface
• Bonds are weaker and less consistent

High Surface Energy Materials

• Liquids spread evenly
• Stronger molecular attraction
• Improved adhesion and durability

Most rubbers, foams, and polymer‑based materials naturally have low surface energy, making them difficult to print or bond without surface treatment. Corona treatment increases surface energy so adhesives and inks can perform as designed.

Types of Corona Treatment Used in Converting

There are multiple surface‑treatment methods used in converting, including flame treatment, plasma treatment, chemical priming, and corona discharge treatment. Among these, corona discharge treatment is the most widely used in roll‑to‑roll converting due to its speed, consistency, and process control.

High‑frequency corona treatment is the most controlled and precise form of corona treatment. It allows converters to fine‑tune treatment levels for uniform surface energy across the entire web—especially critical for demanding adhesive and printing applications.

TPC Converting’s High‑Frequency Corona Treatment Services

TPC Converting offers high‑frequency corona treatment converting services for materials supplied in sheet or roll format. Our process introduces ionized gases to the material surface and applies controlled voltage to modify surface energy with precision and repeatability.

Key Benefits of TPC’s Corona Treatment Capabilities 

• High‑frequency corona treatment
  Provides consistent, controlled surface modification for demanding converting applications. 

• Wide‑web corona treatment up to 62 inches
  Allows us to corona treat most extruded or coated substrates without secondary slitting, reducing handling, cost and lead time. 

• Inline converting integration
  Corona treatment is performed as part of our converting workflow, ensuring surface preparation is optimized for downstream adhesive or printing processes. 

• Adhesive and ink compatibility
  We corona treat materials intended for both adhesive bonding and printing applications. 

• Dyne level testing 
  After corona treatment, we can test the dyne level of your material for a repeatable process. 

TPC performs corona treatment every day, making it a core converting capability rather than a limited specialty service. 

Materials Commonly Corona Treated at TPC Converting 

Corona treatment is especially effective for materials with inherently low surface energy. At TPC Converting, we most commonly corona treat: 

• Rubbers 

• Foams 

• Polymer substrates 

• Extruded materials 

• Coated substrates 

Rubbers and foams are among the most challenging materials to bond due to their low surface energy. Corona treatment transforms these surfaces into bond‑ready substrates without affecting mechanical performance. 

Why Choose TPC Converting for Corona Treatment Services?  

If your application involves difficult‑to‑bond materials, materials with low dyne levels, unreliable adhesion, or inconsistent print quality, corona treatment is essential. 

TPC Converting combines: 

• High‑frequency corona treatment technology 

• Wide‑web capability up to 62 inches 

• Daily production experience 

• Dyne level testing 

• Deep expertise in adhesive and ink‑based converting 

This allows us to deliver consistent, high‑quality surface treatment that improves adhesion and expands what’s possible with challenging materials. 

Need Corona Treatment for Your Next Converting Project? 

Contact TPC Converting to discuss your material, application, and surface‑energy requirements. Our corona treatment services help ensure your adhesives and inks perform exactly as intended.