The vast majority of people involved with offset printing are well aware of how the image is formed. We have talked about it in our articles too. However, the main problem with offset printing has always been the difficult-to-control application of the dampening solution to the plate. That’s why manufacturers of printing machines have always thought about how to improve the process.

The first attempts to get rid of dampening in offset printing date back to the mid-60s. This is how a trend called Waterless Offset Printing came into being.

3M developed the first waterless offset plates as an alternative to traditional offset to avoid problems with dampening solution and thus improve print quality. The main reasons why engineers were looking for a waterless solution were:

1. Problems with the water-colour balance

In classic offset, the wetting solution must be precisely dosed, otherwise blurred areas, ink emulsification and colour instability occur. The most common at the time were dampening units were equipped with plush rollers. It was exceptionally difficult to obtain a stable film.

A small change in temperature or in the composition of the moisturising solution had a dramatic effect on the print. To combat the effects of temperature, some ink temperature control (ITC) devices appeared in printing machines.

2. The desire to improve print quality

Without water, the ink is more evenly layered, providing more contrast, saturation and detail.

This is especially important for highly artistic and accurate colour reproduction (e.g. for multi-colour works).

3 Environmental and economic benefits

The elimination of chemical components (isopropyl alcohol and other substances in the moisturising solution additives) reduces harmful emissions into the atmosphere.

The quicker the print is ready, the less paper is used for finishing.

Who pioneered waterless offset?

The first waterless offset printing plate was invented by the American company 3M in 1968. It was a special plate with silicone surface that repelled ink from the non-imprinting elements. After exposing the plate, the silicone was washed off the printing elements and remained on the whitespace elements. However, the technology did not become widespread until the 1970s, when the Japanese company TORAY Industries refined the idea and began commercial production of waterless offset plates. These became the standard for waterless printing and are still in use today.

The role of key companies in the development of the technology

3M (USA) – pioneers of waterless plates

In 1968 the company developed the first waterless plate. Several problems were encountered both in the development of suitable inks for this process and more importantly, in the durability of the driography plate. After several years of research and development and many millions of dollars invested, 3M chose not to pursue further development of the product. The technology was not a commercial success as it required expensive special inks.

TORAY Industries (Japan) – the first mass producer of waterless plates

In 1972, Toray Industries, a large Japanese company specializing in synthetic materials development and manufacturing, purchased the patents for the waterless products from 3M. Related patents were also purchased from the Scott Paper Co., who were working on a similar project.

Toray’s experience in working with synthetic materials and advanced polymer compounds allowed them to improve on the original product design. After some five years of research and development, the Toray Waterless Plate was introduced at DRUPA in 1977 and became the industry standard.

Presstek (USA) – digital waterless printing

In 1987, the company developed a waterless offset analogue solution using laser exposition. Their DI (Direct Imaging) technology allowed for printing without lay-up, which made waterless printing convenient for small runs.

Heidelberg (Germany) – introducing waterless offset to the industry

In the 1990, the company started to produce waterless printing machines called GTO-DI and later – Quickmaster 46-4 DI (developed together with Presstek).

Heidelberg found promise in the new Presstek’s technology and offered new plates for its GTO-DI machine and later unwindable polyester webs with a laser burned silicone layer, which were used in the Quickmaster 46-4 DI.

However, Heidelberg later abandoned purely waterless technology in favour of Anicolor, which used the advantages of traditional offset but with minimised moisture problems. Presstek continued to produce plates for the Ryobi 3304 DI and for the in-house developed press even when Heidelberg became disillusioned with the technology and discontinued their machine.

Koenig & Bauer (KBA) (Germany) – an attempt to create an industrial waterless offset press for printing multi-colour work

In 2004, KBA (Koenig & Bauer) showed at DRUPA the KBA Rapida 74 printing machine with a Gravuflow technology without the usual ink rollers. This was an attempt to create an alternative to standard offset using waterless technology. It used an engraved anilox roller that fed a strictly metered amount of ink. However, the technology did not become widespread due to the high cost of materials and difficulties in printing large runs.

Rapida machines, especially the Rapida 74-6+L versions, are still on the market today and stand out for their very low price. When buying such a machine, some used equipment dealers avoid mentioning that this machine does not have the classic rubber rollers and try to attract the buyer with the low price of the machine. If a buyer accidentally purchases such a machine out of ignorance, he will face serious difficulties.

A little later came printing machines such as the Genius 52 and Karat 52.

Why did many companies experiment with waterless offset in the 90s-2000s?

Problems with conventional offset

Conventional offset requires precise control of dampening – even small changes in temperature or solution chemistry can cause print instability.

Set-up times and paper waste were significant, especially for short runs.

Popularity of waterless technology

Waterless offset offered better colour control as there was no wetting solution to dilute the ink.

Reduced environmental pollution as no chemicals were used to regulate the moisturising solution.

The Japanese company Toray developed waterless offset plates and many printing machine manufacturers (Komori, KBA, Heidelberg) began adapting them to their systems.

Limitations of waterless offset

• Expensive consumables – waterless plates were more expensive than standard plates.
• Temperature sensitivity – the machine could produce unstable results when heated.
• Non-universality – it was impossible to print on all types of paper, especially on absorbent materials.

Why didn’t waterless offset become the standard?

Despite the interest in the technology, traditional offset remained more versatile and digital printing was getting better. Therefore, waterless offset never replaced classic methods, and technologies such as Heidelberg Anicolor became more viable alternatives.

While waterless offset has a number of advantages, it also has serious disadvantages:

• High plate price – waterless offsetplates are much more expensive than conventional plates. Requires special equipment to develop them.
• Sensitivity to temperature – printing is unstable even with a slight increase in temperature inside the machine.
• Limited choice of inks – requires a special low tack ink capable of being fed through an anilox rasterised roll.
• Non-universality – you can’t print on all types of paper.

Therefore, the technology has not replaced traditional offset, but has found limited use in premium printing, document security and low-volume offset printing.