Color digital printing is approaching offset printing

Digital color printing has gone through a decade, using solid or liquid colorants (Toner) for printing on digital presses instead of conventional offset printing inks. At the 1993 IPEX (International Printing Equipment Exhibition), indig and Xeikon's first digital press debuted, but it wasn't until Drupa in 1995 that two digital presses were available. At Drupa, Heidelberg introduced the new digital product Quickmaster 46-4 on-machine direct imaging press, but its printing method is still four-color offset printing, printing quality is better than digital printing, and the operating cost is lower. It can be said that Heidelberg's DI printing machine (directly in the press like a printer) has slowed down the approval process of color digital printing presses in the printing industry.

There are many problems with early color digital printers that limited the range of color digital printers. Although beautiful color images can also be printed, stripes or bands often appear, and even some colors can cause color casts. In addition, color digital printing also has certain limitations in the printing materials. It can only use several kinds of paper or a few substrates. It has been found that the advantages of color digital printing machines are short lived colors, and it is also suitable for personalized printing.

After 1995. The color digital printing market is booming. All manufacturers have improved their own equipment, with higher quality and reliability, and lower operating costs. Xerox launched the Docucolor 2000 series of color digital printers at the end of 1999, and leapt to the top of the digital press sales list with its outstanding advantages of “high performance, high quality, and low cost”, becoming the best-selling model at the time. Japan's Canon company entered the market with the GLO 1000 digital press and sales were good. Although the color effects of various color digital printers are excellent, especially the Hp Indigo's new Turbostream model, digital prints still look inferior to offset printing. The color of digital prints is too bright and the picture looks rough. Observing from a certain angle, the images on the digital color prints have a feeling of rising from the surface of the paper. This is because most of the colorants accumulate on the surface of the paper, and the offset oil

Color digital printing pigments that are deeply in the human ink can seep into the interior of the paper, and this is even more noticeable with very coarse solid colorants.

At Drupa 2000, color digital printing has been recognized by the industry, and the installed capacity of equipment has exceeded 10,000 units worldwide. In order to make color digital printing truly enter the commercial printing field, its print quality must reach or be close to offset printing. Digital press manufacturers have mastered the manufacturing technology of high-quality digital presses, and have quickly studied and introduced corresponding technical solutions. Since Drupa 2000, there have been new models on the market, and their print quality is no less than conventional four-color offset printing. This is because the color gamut of CMYK colorants is broader than that of offset inks, which means that digital presses have exceeded the four-color offset press in color reproduction range.

Drupa 2004: Color Digital Printing Challenges Offset Printing

At this year's Drupa, color digital printing will pose a real challenge for four-color offset printing in the short-run commercial printing market with a volume of around 3,000. Heidelberg's NexPress 2100, HP Indigo Press 3000, Xerox Docucolor 6060 and iGen3 presses are just as print-ready as offset prints, and may attract widespread attention. Heidelberg and Xerox's digital presses use finer colorants, which require almost no contact when the colorant is transferred from the surface of the media to the paper and have a lower melting temperature on the paper, so that a high quality printing effect can be obtained. The HP Indigo model adopts six-color or seven-color printing instead of conventional four-color printing, and the printing quality is closer to offset printing, and it is far superior to other digital printing machines and many offset printing machines in color gamut reproduction. However, there is a defect in this type of machine. The printing effect on light coated paper or non-coated paper is not ideal.

Since its introduction, color digital printing has been doing its best to catch up with offset printing. The appearance and feel of offset printing is the standard for color commercial printing, and it is also the effect desired by print buyers. At Drupa 2004, we will definitely see the above-mentioned digital presses print "offset-like" prints, and we may also see other models' outstanding performance. I personally look forward to Canon's ability to exhibit new models that are superior to existing products at Drupa.

Digital, Colour Lite: The Threshold for Decreasing Digital Printing

In the past year, a major development in the field of color digital printing was the so-called “DigitaI Colour Lite” digital press. Many Japanese suppliers introduced this type of product with a slightly slower printing speed but excellent print quality. The speed of this digital press is about 30 pages/minute and it sells for less than 50,000 euros. New technological breakthroughs have been made in the use of colorants in digital printers of this type. New colorants are not made from large pieces of material, but are chemically prepared, with finer, more uniform particles, and better flowability. This means that the amount of grease can be greatly reduced. As we all know, after reducing the grease, the gloss of the printed matter is weakened and it is closer to the offset printing effect. Today, chemically prepared colorants are used only in the Digital Colour Lite low-speed printers of Konica and Xerox. Other high-speed digital printers have not yet adopted this technology.

At this Drupa, the printer should be very concerned about Di91ta [ColourLite digital presses, the quality of their prints can be comparable with offset printing, in the future may become a very strong competitor. Therefore, I estimate that some companies and in-house printers may install such digital presses and print short prints with prints of around 200 prints. This type of color digital printer will have a popular trend in the future.

Application of inkjet digital technology

The digital color printing technology exhibited at Drupa in 2004 may be far more than this. We will see the inkjet printers from SaiJin Digital Printing Co., Ltd. using continuous inkjet technology, which can print 2000 A4-format color prints per minute. With the latest printheads, the color print quality is close to that of newspaper offsets, and the print volume is large. The cost of the batch is low. Many market participants may be interested in this inkjet printer. Also in the inkjet field, Drupa will present several digital presses that use drop-on-demand technology. They will compete fiercely with offset and screen printing in the field of label printing. In fact, many posters and labels have turned to color inkjet digital printing technology. Inkjet printing technology will also appear in the short version of the carton processing production, which is also a major challenge to the traditional carton offset printing technology. In addition, inkjet digital printing has appeared in the field of composite flexible packaging printing, and its quality has reached the effect of gravure printing.

Cost is the key

If printing companies are planning to invest in digital printing, a key factor to consider is cost. The first thing to consider is the cost of operation, followed by the cost of equipment. In many cases, the cost of a digital press is very different from that of offset printing. Many digital press manufacturers will offer a quote method called A Click Payment. Each print requires a one-button payment from the equipment supplier. This may include the overall operating cost of the digital press. But usually it also includes equipment maintenance. Machine idle and technical support costs, in which case the cost of the colorant is additionally accounted for. The cost accounting method of Heidelberg's NexPress press is different from the one-click payment. The cost of colorants, accessories and technical support is separately accounted for as needed. Although the main components of digital presses need to be replaced frequently, there are still big differences between digital presses and offset presses. For example, manufacturers recommend replacing the imaging drum and the drive drum that cover the organic photoconductor every 250,000 prints. For a full-load digital press, it means that it will be replaced once a week. For one-touch payment type digital printers, the replacement cost of parts has been included in the one-click payment price; for NexPress digital presses, these accessories have to be paid extra. If a printing company is evaluating the price of a digital press, then you need to fully understand the different pricing methods. Regardless of which digital press is used, it is necessary to achieve a print volume of over 3,000 prints, and its running cost can compete with offset printing. However, it is difficult to accurately calculate the balance between digital printing costs and offset printing costs. Experts have their own opinions on this issue.

Drupa 2004 will be a big stage for competition in various color digital printing technologies. At the same time, it can also take the opportunity to measure whether digital printing technology has the ability to challenge traditional printing in terms of quality and cost. At the upcoming exciting Drupa exhibition, digital printing technology will be one of the focuses of much attention.