There are several ways to print on a cup. These are pad printing, screen printing, or inkjet printing. Let’s review some important questions before deciding on the best method to print on cups.

1. The substrate: what material is the cup made of?

Digital printing is versatile; however, it cannot print on some substrates, such as silicone. For silicone cups, screen printing or pad printing are the best options for printing on this material.

2. The size of the image: do you need 360-degree full-wrap graphics?

Pad printing prints about 20–30% of the drinkware. Digital printing, on the other hand, can print full 360-degree images.

3. Type of graphic: How many colors do you need to print?

Pad printing and screen printing can only print one color at a time. With pad printing, it is possible to print up to six colors. On the other hand, with digital printing, it is possible to achieve full-color photographic prints.

 

Equipment and supplies are needed for pad printing on cups.

1. Pad printing machine

Choose the number of colors and the maximum image size.

2. Pad printing ink

The substrate you are going to print on dictates the pad printing ink to use. For example, if you are printing on glass, the best ink to use is the MG series.

3. Printing pad, cup, ink cup ring, and plate (cliché)

These products are all components of a pad printing machine. The silicone pad printing pad size should always be 20% larger than the image size. Additionally, you should choose the pad depending on the product and the overall print goal. For example, use a hollow pad if you are printing pint glasses or short glasses. With a hollow pad, you will get a slight wrap. The machine determines the ink cup and ink cup ring. Generally, a 90-mm ink cup will fit on a 90-mm pad printing machine. Therefore, you cannot use a 150mm ink cup ceramic ring on a 90mm ink cup machine. Finally, select the pad printing plate based on the machine size, as it holds the artwork. After etching the plate, place it on the machine for printing.

 

4. Pre-treatment

Some products, such as polypropylene plastics, require pre-treatment. This can be in the form of a flame, corona, or chemical (PP primer—wipe on primer).

5. Drying

Many of the inks for pad printing will air dry over time. However, for products that need to achieve optimal adhesion, heat is required. Examples include glass, metal, and silicone substrates.

6. Tooling and printing fixtures

Users utilize tooling fixtures to register the product. These pad printing fixtures enable users to consistently print the same place. Fixtures are critical when printing more than one color.

Component for digital printing on cups

1. Machine

There are two main types of digital machines to choose from. The best option is a cylindrical printing machine. The other option is a flatbed printing machine equipped with a “kebob” attachment. A flatbed printer is slower and offers less vibrant prints compared to a specialized digital cylinder printer. The Gyra® digital cylinder printer prints high-quality, full-color graphics directly onto cups, glasses, and other cylindrical products.

2. Ink

UV ink is one of the most important inkjet printing supplies. Just like pad printing, the UV printer ink in digital printing will depend on the substrate that you are printing on. For example, the best UV ink for glass is the 314 Series UV ink for glass. For flexible items such as HDPE cups, the best ink would be the 160 Flexible UV ink for digital printers.

3. Pre-treatment

Printing with UV inkjet inks requires pre-treatment for quite a few items, unlike pad printing. For example, glass requires flame treatment. Alternatively, using the Natron G1 glass primer ensures that the printed glass will pass wash testing. For the pre-treatment of stainless steel, use the M74F UV adhesion promoter.

4. Fixture

Like screen and pad printing, fixtures are key for digital printers—both cylindrical and flatbed printers. The fixture securely holds the cup in place during the printing process.