At present, whether it is traditional Chinese paintings, oil paintings, or advertising paintings, as long as it is carried out with layers, especially the color of the skin that expresses the screen, color separation and screen printing are used. The screens are offset, gravure, and flexo (flexographic). Copy from the printing, but there is also a version of the Muara, woodcut watermarks, screen printing without dot printing.
1 Dot printing There are two types of dot printing for color image levels:
1.1 AM Screen Printing Screen printing refers to the use of dot size to represent the depth and depth of an image within a unit area, but it has a weakness that is prone to moire.
1.2 FM network screening printing With the increase of computer computing capabilities, FM mesh screening technology has emerged. FM screening technology is consistent in the unit area of ​​the size of the network, the number of points is the density of the image to show the shades of light and shade , FM network outlets basically solved the problem of moire.
The above two screening methods use offset printing, gravure printing, embossing, or screen printing. If you want to represent the level of the image, you cannot leave the outlets. Look at the printed matter with a magnifying glass, whether it is the AM screening technology or the FM network. Thanks to the screening technology, outlets are clearly visible on the replicas, so they are certainly replicas, and they cannot be made in any way.
2 No dot-level printing No dot-level printing, there are currently three ways: the Mi Luo printing, woodcut watermark printing, silk screen printing.
2.1. Feiluo Printing Feiluo Printing is a kind of early photolithography technology that was invented. It uses glass for plate printing, also called glass printing. Its craft is:
2.1.1 Grinding Glass The polished surface of 10mm thick glass is ground, cleaned and dried and then coated with a primer.
2.1.2 Coating
The ground glass is then coated with a mixture of sodium silicate and protein solution and the liquid is used as a primer layer, dried, and coated with a photo resist.
2.1.3 Coat the photoresist on a dry substrate and apply a layer of dichromate and alum enamel on the substrate. Then dry. The drying temperature is between 40°C and 60°C. Photoresist produces fine wrinkles.
2.1.4 Shaiban Consecutively adjusted negative film negative film and photosensitive film close exposure development. The unexposed photoresist was washed away during development and a water-absorbing layer was formed during printing. The light-sensitive part of the photosensitive adhesive, due to different levels of sensitive photosensitive photosensitive depth is also different, the thickness of the ink-absorbing layer is not the same.
2.1.5 Printed on a dedicated platform. The structure is a flat, circular press with a roller. The applied ink requires good fluidity and low viscosity.
Because the Feiluo printing is a negative film printing plate, the greater the amount of light on the printing plate image, the greater the hardened layer, the more wrinkles, the more ink amount is adhered, and the darker the color is when printing. On the contrary, the brighter it is.
Although Minami printing is recognized as a dotless printing method in the world, it is difficult to reproduce fine images due to insufficient levels. In Japan, there is also a print version of the Jeollas. Only prints such as certificates are made.
2.2 Woodcut Watermark Printing Woodcut watermark is the invention of our country. It is my traditional printing method. It is recognized in the world and its process:
2.2.1 trace (color separation).
(1) When enveloping, mask the transparent and impervious film paper on the original, and then copy the picture faithfully on the film.
(2) The gannet paper is then smeared into the paper on the manuscript, and the colors are separated according to different hue. The dots, lines, color blocks, inscriptions, seals, and picture layers are each described as a piece of manuscript. How many shades of the original artwork are described in the number of drafts.
The technicians (some painters) who undertake sketching not only must have high painting skills, but also have a profound knowledge of Chinese painting. When making a sketch, you need to make decisions about how the original is shaded, the painter's style and artistic characteristics, and the size of the screen.
2.2.2 Engraving a woodblock Posting a manuscript on a wooden board. After being solidified, it can be carved and plated. Each manuscript is carved into a wooden board, and printing a painting requires engraving dozens or even hundreds of plates. The sculptors must be familiar with the paintings and paintings of ancient and modern times. They must be able to experience the original work carefully and be able to sculpt their lines and layers in a meticulous manner.
2.2.3 Printing The carved wood plates are brushed in sequence. The method is to first brush the ink on the protruding portion of the woodblock (that is, the screen portion), then lay the rice paper on it, and then hold the brush to print on the rice paper. How many pieces of woodblock were printed on this rice paper, and the final product was made.
But brushing is not an easy task. It requires the brusher to be familiar with the painting techniques. Before brushing, it is necessary to analyze the speed, slowness, lightness, and weight of the original pen, and use the thick, light, dry, and wet colors. Different, in the brush printing process, but also according to the original rendering touch-up, etc., while brushing and brush the appropriate processing, so that brush prints reproduce the original ink characteristics.
2.3 Silk screen printing and printing screen printing can be done without copying Chinese paintings, oil paintings and advertising paintings. The process method:
2.3.1 Layered Separation of Originals The originals are divided into multiple slices at different levels of yellow, blue, green and black by computer. If you can divide each color into 10 levels, you can separate 10 different levels of negatives for each color.
2.3.2 screen printing plate number will be 40 negative film number, into 40 screen printing plate. The requirements of this printing process on the tension of the stretch net, the choice of the screen, the application of the photosensitive adhesive, the exposure time, and the development should be basically the same as those for the screen printing.
2.3.3 Printing According to the screen number of different layers of film drying out, in order to print, this printing method is called layer printing, someone called ladder printing, the actual level is printed from shallow to deep layer . It can not only achieve the purpose of the performance level, but also achieves no dot-printing, which can be used as a real thing. For example, copying ancient paintings in France in this way gives true artistic value. The French oil painters entrusted their own oil paintings to the screen printing company. After printing and copying at the silk screen level, they were signed by the painter to give it a collection value.
3 Screen printing will be the development direction of future dotless printing. Offset printing, gravure printing, embossing, and screen printing of the FM network mentioned above. Because replicas have outlets, they cannot be used in an elegant manner. Luoban printing has gradually been eliminated due to lack of space, limited space, and small print.
Although woodcut watermark copy images can achieve real effects, they have a long production cycle, less printing, and high cost. However, the process of sketching, adjusting and printing is complicated and the manual operation has many ingredients. Although the technicians are experts, each The color tone is also difficult to achieve the same, it is easy to cause color cast, at the same time there is also overprinting is not allowed. Deformation and other issues.
In the final analysis, the competition of printing companies is based on science and technology and talents. The continuous application of new technologies, new processes, new materials, and new equipment by screen printing companies has brought about rapid development of screen printing technology.
Since the screen-printing layer uses modern tools such as computer to analyze originals, scan originals layer by layer, and output layered negatives, and then prints through the silk screen version and layered printing, its copied handicrafts are highly accurate and with rich subtle layers. The reproducibility is good, not only can it be compared with the dot-printing glue product, but also can be compared with the non-dot-like Muara version and the woodcut watermark.
Nowadays, due to the increase in the collection of works of art and the continuous improvement of the appreciation ability, it is particularly love for the genuine products of ancient paintings and oil paintings, and there is only one genuine product. How can we satisfy people's needs? In comparison, only the screen-level (no dot) printing can make the image delicate, rich in layers, strong in three-dimensional sense, and the ink layer can be thick and thin. Offset printing is generally 3-4 um, and the thickness of the screen printing ink layer can reach tens of tens Micron, can make the image prominence, especially for the oil painting can really maintain the original artistic charm, to maximize the effect of the original, so that the network printing technology dot-less printing will be the future direction of replication of Chinese painting, ink development. (Zheng Dehai)