The advantages and disadvantages of several Paper Cigarette Boxes without dot layer printing processes are analyzed

The advantages and disadvantages of several Paper Cigarette Boxes without dot layer printing processes are analyzed

 

Whether it is traditional Chinese painting, oil painting, advertising painting, as long as the layers are carried out, especially the performance of the skin color of the picture is the original color separation and screen printing, through offset printing, gravure printing, relief printing (flexographic printing) screen printing copy, but at the same time there are collotype plate, woodcut watermark, screen plate without dot printing.

 

Dot printing

There are two points of dot printing that represent the color image level

Amplitude modulation dot screen printing: refers to the unit area, with the size of the dot to represent the depth of the image, its weakness is easy to appear moire.

 

Frequency modulation dot screen printing: with the increase of computer computing function, there is a frequency modulation dot screen technology, frequency modulation dot screen technology is the same size in the unit area, the number of dot is the density to show the depth of the image light and dark level, frequency modulation dot basically solves the moire problem.

 

The above two screening methods, whether using offset printing, gravure, letterpress or screen printing, to express the image level are inseparable from the dot, with a magnifying glass to look at the print, whether it is amplitude modulation dot screening technology, or frequency modulation dot screening technology, the dot is clearly visible on the copy.

 

No dot level printing

No dot level printing, there are three methods: collotype printing, woodcut watermark printing, screen plate level printing.

 

Collotype printing is a kind of photolithographic printing technology that has been invented for a long time. It uses glass to make plate printing, also known as glass plate printing. The process is:

Grinding glass: The smooth surface of 10mm thick glass is ground, and the bottom layer is coated after cleaning and drying.

Coating the bottom layer: the ground glass is coated with a layer of sodium silicate and protein liquid mixture and liquid as the bottom layer, after drying, and then coated with sensitive adhesive.

 

Coating photosensitive glue: on the dry bottom layer and then coated with a layer of bichromate and Mingjiao photosensitive liquid on the bottom layer, and then dried, drying temperature between 40℃-60℃, drying, sensitive glue will produce subtle wrinkles.

Printing: The continuous adjustment of negative film and sensitive film close exposure development. The unexposed photosensitive glue is washed away during development, and an absorbent layer is formed during printing. The photosensitive glue of the light-receiving part has different depth of sensitivity due to different levels of photosensitive glue, and the thickness of the ink absorbing layer is not the same.

 

Printing: Printing is carried out on a special platform with collotype printing press, its structure is round pressed flat and inked with a rubber roller. The applied ink requires good fluidity and low viscosity.

 

Collotype printing is the use of negative negative plate, the more light on the plate image of the part of the hardened layer will be larger, more wrinkles, more ink adhesion, the darker the printing tone, vice versa, the brighter.

 

Although collotype printing is recognized as a type of no-dot printing in the world, it is difficult to reproduce fine images due to the lack of fine layers. Japan also has collotype printing, which only makes printed items such as certificates.

 

Woodcut watermarking is the invention of our country, is my traditional printing method, recognized in the world, its process:

tracing

(1) When painting, first cover the original with a fully transparent and impervious film paper, and then copy the picture on the film paper as it is painted.

 

(2) The wild goose paper is covered in the film paper that is traced into the manuscript, and the color is separated according to different colors, and the points, lines, color blocks, inscriptions, seals and picture levels are traced into a manuscript. The number of shades on the original work is traced into how many manuscripts.

 

The technician of drawing should not only have high painting skills, but also have deep attainments of Chinese painting. When painting, it is necessary to decide how many blocks of the original manuscript, the style and artistic characteristics of the painter and the size of the picture, and how to print.

 

Engraving block: the manuscript is posted on the board, to be dry and solid can be carved into the plate, each manuscript carved into the board, printing a picture to carve dozens of pieces, or even hundreds of plates. The carving personnel must be familiar with the ancient and modern painting theory, and seriously understand the original work in order to operate freely and confidently carve the lines and levels beautifully.

 

Printing: Brush the carved block in turn. The method is to brush the convex part of the block (that is, the picture part) first, and then spread the rice paper on it, and then hold the brush and brush on the rice paper. How many blocks are printed with this rice paper, and finally finished. It requires that the brush printer must be familiar with painting techniques, before the brush printing to analyze the original brush speed, slow, light, heavy, thick, light, dry, wet and other different colors, in the process of brush printing, but also according to the original rendering and polishing, brush and then appropriate processing, so that the brush printing product reproduces the brush and ink characteristics of the original.

 

Screen plate layer printing can do no network copy Chinese painting, oil painting, advertising painting. Its process method:

Stratified color separation of the original manuscript: the original manuscript is divided into multiple pieces according to different levels of yellow, fine, blue and black through the computer. If each color can be divided into 10 grades, each color can be divided into 10 different levels of negatives.

 

Screen printing: 40 negatives are numbered and printed into 40 screen printing plates. The requirements of this printing process for elements such as the tension of the stretched screen, the selection of the screen, the coating of the photosensitive adhesive, the exposure time, and the development should be basically the same as those for the production of fine screen printing.

 

Printing: According to the screen plate number of different layers of negatives, printing in order, this printing method is called layer printing, some people say ladder printing, in fact, the level is printed from shallow to deep layer by layer. It can not only achieve the purpose of expression level, but also achieve no dot printing, which can be fake and real, such as copying ancient paintings in France in this way, and give real artistic value. French oil painters will entrust their oil paintings to screen printing companies, using this method of screen plate layer printing copy, and then signed by the painter, so that it has a collection value.

 

Offset printing, gravure printing, letterpress printing and screen printing of the above frequency-modulated dots cannot be put on the map because of the reproductions with dots, while collotype printing without dots is gradually eliminated due to the lack of layers, limited space and small print volume.

 

Although the woodcut watermarking copy image can achieve the effect of the fake, but the production cycle is long, the printing amount is small, the cost is high, and the writing, adjustment, printing processes are more complex and many manual operation components, although the technical staff is an expert, each hue is difficult to achieve consistency, easy to bias color, there are also overprinting is not allowed, deformation, etc.

 

Screen plate layer printing uses computer analysis of the manuscript, layered scanning of the manuscript, the output of layered negatives, through screen printing and layered printing, the reproduction of crafts with high precision, rich fine layers, good reproducibility, not only with dot printing products can not be compared, that is, no dot collotype, woodcut watermark can not be compared.