Advantages and disadvantages of offset printing and digital printing.

 Since the creation of Réflexiel in 1993, we have thought of Service Global by offering you complementary offers to our primary activity of mail routing.
So upstream the printing of all types of documents whether they are mail-related or not.

Offset printing

A so-called flat printing process, the printing and non-printing elements being on the same plane. (The offset process uses the antagonism between water and ink to carry over the inked parts to the paper.)

Offset press

The offset comes from lithography and metallography. Between 1860 and 1880, various French printers used the principle of the double decal to print on tinplate, but it was not until 1904 that the American I. W. Rubel exploited this process industrially. The printing forms, generally zinc or aluminum plates, are obtained by photomechanical transfer of the printing elements; currently, they are delivered pre-sensitized to printers, who can use them directly, without prior treatment, for copying. The printing elements are grouped together by a montage of negative or positive films of texts and illustrations. The principle of copying lies in exposure under a light source which changes the characteristics of the photosensitive layer located under the transparent parts of the films. Appropriate treatment allows the transfer of the printing elements from the assembly to the printing form.

On the offset press, the plate is fixed around a cylinder. Its surface is first wetted by a wetting device, then inked by the ink rollers. She transfers the ink from the printing regions onto a rubberized canvas (the blanket), wound on a cylinder, which in turn transfers the print to the paper.

Offset is the most widely used printing process: around 80% of the market. Offset presses operate either discontinuously (sheet-fed machines) or continuously (so-called rotary machines).

A continuous web press will have a paper reel as input and either a reel or continuous screens at the output. These output items will then be customized with variable items on a continuous printer. A sheet press will input a roll of paper and output the almost finished or finished product, such as a newspaper or a brochure for example.

In summary, we can speak of an impact technology, the printing form is produced once, on an offset plate or a flexo cliché for example, fixed on a press, and reproduced thousands or millions of times on paper.

Disadvantages

For an uninformed person the a
mount of knowledge to understand the offset chain: realization of the DTP file which must for example be in CMYK and not in RGB and other details, the adequacy between what to print (characteristics and volume) and the format of the press, the possibilities / subtleties of wedging, shaping, etc.

The constraint of formats. Each document format corresponds to a format or a machine type. Printers, given the costs of acquiring machines, are therefore forced to limit themselves to formats and types of machines. For example offset sheets in 50 x 74 or in 70 x 102, 1 color group or 2 or 4, with or without an additional group for the machine varnish. Or more groups, in reprint ... For types, sheetfed offset, sheetfed web press, continuous web press, each type having its specificities ...

Implementation deadlines

Set-up costs

Paper loss of at least 300 sheets at each registration

No possibility of customization, printing of a single document in n copies.

Benefits

As long as there is no customization, it is the most economical system in case of volume.

In sheetfed offset, the print quality depending on the work to be done can remain superior. Notion of screen, Gamut, adjustment of the ink flow when setting and during printing, the fineness of the ink point. Note that research labs are making progress on nano-ink, which is one of the major points in the long term in offset / digital competition for the benefit of the latter.

Quality of solids

The print quality also remains higher because offset printing uses inks that are prepared before printing.

There are CMYK primary colors (cyan, magenta, yellow, black) and additional pure Pantone colors in direct tones as well as special inks like metallic, invisible, scent, scratch-off, etc. A digital printer is unable to generate a Pantone because she does not know how to work other than on her primary colors alone or by mixing them.

In-line protective acrylic varnish and total or selective UV varnish to enhance your presentations

The types, sizes and weight of paper. More paper choices, larger sizes, smaller or larger weights, there are virtually no restrictions.

Digital printing

Digital printing processes are a natural evolution of printing. After the "first revolution" of the printing press (during the Industrial Revolution in the 19th century, with the invention of the linotype), it is a "second revolution", directly linked to the growth of personal computing and digital from 1980.

The processes used include: inkjet (continuous jet or spray jet), electrophotography or xerography, magnetography, ionography, elcography, and thermography.

Given the different processes, we will summarize as follows, technology without impact, the printer form is a set of points which may vary from one page to another, sent from the computer in a continuous flow directly to the printing system.

These dots are then translated into electrical pulses and toner deposits or ink droplets on the paper.

Disadvantages

If it seems simple to use, I embed a file I click and print, it is not really if you want to print quality. This apparent simplicity for you customers can be the source of disappointments such as what I see on the screen is what is going to be printed. Except the user screens are not calibrated. Likewise depending on the file, rip, paper, toner, fixing system, oven heat and a set of parameters, the results will be very different.

We strongly recommend that, depending on the importance of your document, you move to the registration, failing to agree on the color orientation with your printer.

The paper constraint. To date, outside of roll-to-roll inkjet systems, the majority of sheet-fed printers are limited to the 32 × 45 format.

The choice of papers essentially comes down to offset, digital offset, ½ matt, matt and glossy coated and on weights between 80 and 300g. The papiesrs of creation are to be tested.

The front side is less precise, it is however automatic

The four-color process is obtained by mixing the 4 primary colors Cyan Magenta, Yellow, Black. No possibility for the moment of direct Pantone colors, depending on the paper, we seek the best equivalence of a Pantone, but always by mixing the primary colors. No special ink except the appearance of a white ink which is not very covering and at a very high cost.

Little or no online varnish. When it exists, selective possible and at a high cost.

Benefits

Quick to implement, Print On Demand (POD) concept I print what I want when I want. No waste, no stock, contribution to sustainable development.

You can have the printed documents you want during the day.

Economical for short and medium runs, or even long runs with reel reel inkjet systems.

General print quality depending on the case, equal to or better than the offset.

Excessive customization. The system being managed in data processing, each point can become a variable of personalization.

In addition to the traditional text variables used with black and white laser printers, you can generate any images as variables and even customize within the image.