Die Cutting in PSA Labels: From Stan Avery's Innovation to Modern Laser Technology-Part 1

Ray Stanton Avery

The pressure-sensitive adhesive labels industry owes its existence to a struggling clerk working in a loft above a flower shop in downtown Los Angeles. In 1935, Ray Stanton Avery, who went by name Stan, was living in near poverty, residing in a rented chicken coop while working at the Midnight Mission to pay his way through college. What he created with a $100 loan from his fiancée Dorothy Durfee would transform how products are labeled worldwide and launch an industry that today generates billions in revenue.

 

The Genesis: Stan Avery's Revolutionary Label

Stan Avery didn't just invent the self-adhesive label, he invented the entire machinery to produce it. Using parts from a washing machine motor, a sewing machine, and a saber saw, he created and patented the world's first self-adhesive, die-cut labeling machine. His company, initially named Kum Kleen Products, advertised the ability of these labels to be removed without leaving a mark on merchandise. The first Avery labels were simple, round price stickers meant for gift shops and retailers. In his first six months of operation, sales totaled a modest $1,391. Few could have imagined that this humble beginning would evolve into Avery Dennison, a Fortune 500 corporation with global operations across more than 50 countries and 36,000 employees worldwide.

First die cutter by Stan Avery in 1935

The innovation Stan Avery brought to market solved a fundamental retail problem. Before pressure-sensitive labels, merchants relied on gummed labels that required moistening with water or paste, a time-consuming and messy process. Avery's self-adhesive labels eliminated this inconvenience entirely, creating a faster and more practical labeling solution. His vision extended beyond the label itself to include the machinery for precise die-cutting, which would become the foundation of label converting technology.

By 1940, Avery had moved beyond his humble beginnings and officially started selling his products under the brand name Kum Kleen Price Stickers. The company incorporated in 1946 as Avery Adhesive Label Corporation, and in 1990 merged with Dennison Manufacturing to form Avery Dennison. Throughout his career, Stan Avery received 18 patents for his innovations in pressure-sensitive materials and production technologies. His legacy lives on, not just in the company that bears his name, but in every self-adhesive label produced today.

 The Evolution of Die Cutting Technology

Die-cutting itself predates Stan Avery's innovation by nearly a century. The process was invented in the mid-1800s to help the shoemaking industry. Cutting leather soles for shoes by hand was laborious, time-consuming, and expensive. The invention of the die-cutting machine revolutionized cobbler work, allowing shoes to be cut to consistent sizes and shapes rather than crafted individually. This standardization enabled modern shoe sizing as we know it today.

 Flatbed Die Cutting: The Foundation

The earliest die-cutting machines used in the label industry were also flatbed presses. These hydraulically operated machines use a steel rule die to "click cut" or punch out die-cut parts by driving the die in a downward motion through the material. The flatbed die-cutting press operates much like a stamp, pressing a flat die onto material that sits on a stationary surface, applying even pressure to cut the material into the desired shape with each strike.

Flatbed dies are used with hydraulic or mechanical presses and other lifting systems to press a die down on a sheet of material. They are particularly suited for heavier materials and thicker substrates, making them less ideal for pressure-sensitive labels but excellent for applications requiring precision cutting of rigid materials. Steel-rule die cutting uses a formed strip of hardened steel set into a slotted plywood die-board, with rubber ejectors aiding part release after the cut.

While flatbed die cutting adapted for labels, offers excellent control over each cut and is ideal for intricate shapes with close tolerances, it operates at a considerably slower pace compared to rotary systems. Typical speeds range from 1,000 to 5,000 cycles per hour, making it suitable for small or mid-sized batches but impractical for high-volume label production. The tooling costs for flatbed dies are significantly lower than rotary alternatives, and the ability to make quick die changes makes them valuable for short-run or prototype jobs.

 The Rotary Revolution in Label Converting

The transition from flatbed to rotary die cutting marked a transformative moment in label converting. Rotary die cutting uses a solid cylindrical die that rotates continuously in sync with the web material, paired with an anvil cylinder. The press feeds thin, flexible material, known as web, between these two cylinders. The cutting-edge pinches material against the anvil cylinder, producing clean cuts, perforations, or creases at exceptionally high speeds.

This method revolutionized label production by dramatically increasing throughput. Modern rotary die-cutting systems can reach 10,000 cycles per hour or more, with the fastest machines achieving speeds of 300 meters per minute. The ability to perform inline with printing and other finishing operations means that labels can be printed, die-cut, matrix stripped, and rewound in a single pass, transforming manufacturing efficiency.

A series of gears or servo motors now, force the die to rotate at the same speed as the rest of the press, ensuring that cuts line up precisely with the printing on the material. Rotary presses can incorporate multiple stations that die-cut specific shapes, perform perforations, create creases, or even cut the sheet or web into smaller sections. Some machines use automatic eye registration to ensure cuts and printing align with tolerances measured in fractions of a millimeter, critical for complex label designs and high-quality output.

The economics of rotary die cutting favor high-volume production. While the initial tooling costs are higher than flatbed alternatives, the operational efficiency brings labor expenses down over time. For standardized, repeat orders running into millions of labels, rotary systems offer compelling long-term value and unmatched productivity.

 The Magnetic Cylinder Revolution

While the exact inventor and date of the magnetic cylinder for flexible dies are not definitively documented in available industry records, this innovation transformed the economics and flexibility of rotary die cutting. The magnetic cylinder system addressed a fundamental challenge: solid engraved rotary dies were expensive to manufacture, store, and transport, making them cost-prohibitive for short to medium production runs.

Magnetic cylinders are precision-engineered metal cylinders embedded with powerful magnets, either ceramic or neodymium rare earth magnets, on their surface. They are designed to hold flexible dies—thin, etched steel dies—firmly in place during rotary die cutting. The magnets ensure that every square inch of the flexible die remains securely pressed against the precision-ground cylinder surface, preventing any lifting or shifting during high-speed operation.

Magnetic Cylinder in production

In 2005, Bunting Magnetics launched the X-treme Magnetic Die-Cutting Cylinder, the first magnetic die-cutting cylinder in the world with total run-out accuracy below 40 millionths of an inch (1 micron). This level of precision was revolutionary, enabling clean cuts even on extremely thin materials like 1-mil stock with less than 1-mil liners, on "no-look" labels, and on synthetic materials that previously posed challenges.

The advantages of magnetic cylinders transformed the label industry. Mounting and removing flexible dies takes just minutes, dramatically reducing downtime during job changeovers, particularly valuable in short-run label printing or multi-SKU packaging environments. The cylinders weigh significantly less than solid rotary dies, reducing operator fatigue, machine wear, and transportation costs. Most importantly, they enabled the use of flexible dies, which cost a fraction of solid engraved cylinders and could be stored flat, saving valuable warehouse space.

Today, magnetic cylinders are available for virtually all types of label presses and converting machinery, from brands like Mark Andy, Gallus, Nilpeter, Omet, Rotoflex, etc. Custom designs accommodate a variety of special applications, making magnetic cylinder systems remarkably versatile.

 Flexible Dies: Engineering and Innovation

The development of flexible dies went hand in hand with magnetic cylinder technology. Flexible dies are thin sheets of steel, typically ranging from 0.5mm to 1.5mm in thickness, that wrap around magnetic cylinders and are used for rotary and semi-rotary presses. These dies are produced from specially formulated steel and undergo several sophisticated manufacturing processes.

 Manufacturing Process

Flexible die in production

Production of flexible dies begins with plotting an image directly on the die material. Background material is then removed through chemical etching, and CNC mills create the required cutting or creasing lines with extraordinary precision. The cutting geometry includes profile heights ranging from 0.3mm to 1.5mm and cutting angles that vary based on the material being cut, typically from 30° to 110°.

The manufacturing process includes several optional treatments. Back grinding ensures consistent die thickness. Chemical de-burring smooths edges to prevent damage to the label stock. Most critically, laser hardening and various surface coatings dramatically extend die life and performance.

 

Die Materials and Surface Treatments

Standard flexible dies are CNC-sharpened and feature smooth polished cutting edges obtained using ultra-fine edge polishing techniques. These universal dies are suitable for all types of self-adhesive and single-material products including paper, PP, PE, PVC, PET, Tyvek, thin films on PET liner material, and other materials that are difficult to cut.

Laser hardening represented a breakthrough in die technology. Companies like Kocher + Beck were the first manufacturers in the world to achieve hardness levels of 65 to 68 HRC through laser hardening technology. This process extends die service life by two to three times longer than conventional dies. The laser hardening increases hardness at the tip of the cutting edge based on the carbon content in the steel, creating exceptional wear resistance while maintaining die flexibility.

For extremely demanding applications, chrome-coated dies offer even greater durability. A thin layer of chromium, typically 0.01mm thick with a hardness of 70-80 HRC, enables extremely high running performance with outstanding wear properties. These dies are particularly suited for abrasive thermal and thermal transfer papers used in longer production runs.

Non-stick coatings represent another important innovation. Special onyx or polymer coatings have no detrimental effect on the cutting-edge angle or sharpness while preventing adhesive and ink deposits on the cutting blades. These coatings are food-safe, FDA-approved, and significantly reduce downtime for die cleaning. The reduced friction and perfect resistance to wear enable maximum running performance with a consistently sharp cutting edge.

To be continued to part-2

 

Written by Harveer Sahni, Chairman Weldon Celloplast Limited, New Delhi, January 2026