Choosing a Pad Printing Machine

Total Colour Transfer Pad Printing System

This technique, used almost exclusively in ceramic decoration, combines pad and screen printing. As you can see from the diagram, the image is screen printed onto a special plate, and then the pad picks up the inked image and transfers it fu the substrate.

This technique, developed for printing onto ceramic items, uses a mix of pad-printing and screen-printing technology, as illustrated in Figure 7. These systems don't use etched cliches to carry the image. Instead, the ink or ceramic colour is screen printed onto a flat, siliconecoated plate. The ink rests on top of this plate rather than adhering, and is then picked up by the pad and transferred onto the substrate.

When this process was first developed in the 1950s, the colout- was cold. This did not allow for total transfer, however, so thermoplastic colour was used. This colour is a wax-llke solid at room temperature, which is then heated on the metalmesh screen by an electric current. This raises the temperature of the colour- to 167°F (35-40°C) lower then the Printing ink. The pad Lifts the colour- from the silicone plate and transfers it to the ceramic item, which chills the ink and causes a complete transfer.

Although this process is used almost exclusively in the ceramics industry, it demonstrates the happy marriage of the two processes. Its advantages include the following:

  • Patterns can be printed onto areas and surfaces (e.g.., double curved surfaces) that cannot be directly screen printed.
  • Fine lines and heavy bands can be applied at the same time as the principal pattern in one machine pass.
  • Heavy deposits of colour can be applied to complex shapes. This was previously only possible using screen printing, which could print only on a more limited range of shapes.
  • Screen printing, not pad printing, determines the quantity of colour applied. Therefore, more can be deposited than in conventional pad printing. This ensures prints of consistent high quality. Designs can employ a full range of effects, from solid lines to halftones.
  • Many users manufacture screens in house, whereas cliches must often bed one by a vendor.

Choosing a Pad Printing Machine - Introduction

In the padprinting industry purchasing decisions are often based on asswnptions that are simply nuts - literally.

Manually Operated Pad Printing Presses

Except in cases where pad printing will be done on a very small scale, manual machines are not even entry level anymore. However, some may be useful for testing purposes.

Open Ink Trough Pad Printing Machines

In these original semiautomatic machines, the inking mechanism is mounted above the cliche. Although more modern models ha we better features, contro/lirrg ink condition fluctuations.

Partially Covered Ink Troughs

In these machines, ink is contained in a trough behind the cliche. The ink is pulled forward by a spatula mounted on a horizontal carriage with the doctor-blade assembly.

Sealed Ink Cup Pad Printing Machines

These presses are designed to contain the ink in a cup that is turned upside down and pressed firmly against the cliche, sealing in the ink.

Reciprocating Cliches Pad Printing Machines

In these models, instead of the pad moving back and forth from cliche to substrate, the cliche moves out of the way, while the pad remains stationary.

Rotary Pad Printing Presses

These presses use a rotary drum-type sllicone pad, usually in conjunction with a steel cylinder cllche into which the desfgn is etched.

Total Colour Transfer System

This technique, used almost exclusively in ceramic decoration, combines pad and screen printing.

Carousel Style Pad Printing System

This multicolour pad-printing system uses a cambination of two rotary tables and a rotating pad carousel.

Non-Horizontal Pad Printing

Machines such as this are suited for printing onto surfaces that are vertical or angled.

Computer Numeric Control (CNC)

In presses with computer numeric control (CNC), the substrate is stationary and the pads are programmed to print one image at a time onto the item.

Pad Printing Press Options

Most manufacturers provide a variety of add-ons for their presses.

How to decide what machine to buy

To enable you to judge which press to buy, you will at least need answers to all of the questions shown under Purchasing Considerations.

Pad Printing Machine Purchasing Considerations

Trying to decide which pad-printing machine to buy? Start by answering the following questions.