What is date coding?
Date coding is the process of printing important time-related information – like best-before dates, expiry dates, or production dates – onto products or packaging. You’ll see these codes on almost everything from milk cartons and snack bags to cosmetics and pharmaceuticals.
The main reason for date coding is to help people know how fresh or safe a product is. It also helps manufacturers and retailers track products through the supply chain. If there’s ever a product recall or quality issue, date codes make it easier to trace where and when something was made.
There are a few different types of date codes you might come across:
- Best-before dates (common on food): Tell you how long the product will stay at its best.
- Use-by or expiry dates (often on medical or dairy products): Show when the product is no longer considered safe to use.
- Manufacture or production dates: Often printed on packaging to show when the item was made or packed.
The codes themselves can be printed in various formats depending on the product and local regulations. Some are very simple – just a date like “16/06/2025” – while others include time stamps, batch codes, or even QR codes.
Date coding is done using different types of printers depending on the product, the production environment, and how the packaging is handled. The two most common types are continuous inkjet (CIJ) and thermal inkjet (TIJ) printers.
- CIJ printers, like the alphaJET range from Koenig & Bauer Coding, are designed to work right on the production line. They can keep up with fast-moving bottles, cans, or pouches and print clearly on curved or uneven surfaces. The ink dries almost instantly, so there’s no smudging.
- TIJ printers, which use disposable cartridges, are more often used for flat surfaces like cartons or sleeves – often in offline setups using feeders like the udaFORMAXX. They produce crisp, high-resolution codes.
There are also laser coders, thermal transfer printers, and other specialist machines depending on the application.
Inks used for date coding are chosen carefully to match the surface and the environment the product will go through. For example, food packaging might require food-safe or sterilisation-resistant ink, while drinks bottles might need water-resistant ink.
In some industries, date coding isn’t just helpful – it’s a legal requirement. Regulators want to ensure that consumers know how fresh a product is and that companies can track and trace items effectively.
In short, date coding is a small but vital part of product packaging that helps keep consumers informed, protects product quality, and supports traceability right through the supply chain.