What Are Tagless Printing Plates?
Tagless printing plates, also known as a cliche, are a critical component in the pad printing process. The plate holds the image to be printed. The etch quality and depth will ultimately determine how the final tagless print will look. Careful consideration in choosing the right plate material and etching method will make all the difference. Etching a tagless printing plate requires the need of either chemical etching or laser etching.
Chemically etching a plate requires the use of a photopolymer plate material. Photopolymer is more of a hands-on method of etching a plate. The process requires the artwork to be printed onto a film positive. A film positive is a transparent sheet with the artwork printed on it in complete black. The film positive is placed over the plate and cured under UV light for 5-10 minutes. The exposed plate (not covered by the print on the film positive) will harden.
After the first round of exposure, the film positive is swapped out for screen film. Screen film is a transparent sheet with thousands of tiny dots, available in either 200 lines per inch or 300 lines per inch depending upon how bold or fine the image is. The general purpose of line screen is to add a dot pattern to the inside of the artwork. The dot pattern will improve plate doctoring and image quality as well as reduce the chance of common printing problems such as scooping. The line screen is placed over the plate and is again exposed under UV light for 5-10 minutes.
Once the tagless printing plate has been exposed, the etch must be washed. The wash can either be an alcohol-based washing solution (developer) or a water-wash solution. The wash is determined by the plate material. The plate is then carefully cleaned and the uncured plate material is washed-out leaving a final etched plate. The plate must be dried and free of any moisture before use. Often a plate is placed in a drying oven for 10 – 15 minutes.
Polymer plate-making is a time-consuming process that requires the use of many consumables. It is, however, a much lower start-up cost than laser plate-making. Polymer plate-making has a lot of room for error, therefore it is important to keep exposure times as accurate as possible.
Laser etching a tagless pad printing plate requires the use of a laser engraving machine. Not all lasers are created equally. The most common laser types are Fiber, CO2, and Diode. Each type of laser has unique properties such as power, speed, and dot size. All of which are critical to the etching of a plate.
Regardless of the type of laser plate-maker, the process still works relatively the same. First, a graphic or artwork is created in a graphic design program such as Adobe Illustrator. The artwork is then imported into the laser software. The plate is loaded and the machine starts etching. Depending upon the type of laser and graphic size, graphics will generally take anywhere from 5-20 minutes.
Laser etching a tagless pad printing plate is a more efficient plate-making method than chemical etching. Change the artwork on the fly, no need to use any consumables, and the etching speed is much faster. The quality of an etched laser plate is generally much higher than a photopolymer plate and the artwork is 100% repeatable. In addition, laser plate-making is cost-competitive with photopolymer plate making.
A wide variety of plate materials are available, each with unique properties to facilitate a successful garment print. Choosing the right pad printing plate relies heavily on the type of etching method you are currently using. Are you chemically etching with photopolymer plates? How are you washing out your plate material? Alcohol or water? You will need to get a photopolymer plate specifically developed for alcohol washes or water washes.
Are you using a laser plate-maker instead of photopolymer? What kind of laser do you own? Each plate material is developed to absorb a particular type of laser wavelength. There are specific plates for fiber lasers, most of which are made of a metal material and typically last longer than other plates. Plates for CO2 lasers are etched on a variety of plate materials and can range in life depending upon the material.
Tagless pad printing plate materials can get confusing, so it is important to know how you want to etch them. If the etching process is not something you wish to go through, plate etching services will do the work for you. Simply send the artwork in, and receive a finished etched plate in a few days.
© 2024 Arka international
