Classified explanation of the hottest traditional

There are many kinds of printing methods, different methods, different operations, and different printing effects. The traditional printing methods can be divided into four categories: relief, lithography, intaglio and hole printing

reliefprinting

relief printing is called relief printing, which includes letterpress and rubber printing, when the printing surface is prominent and the non image part is concave

letterpress was developed from early clay movable type, woodcut movable type and lead cast movable type. Until modern times, most of it was based on type typesetting. At the same time, this kind of printing method belongs to direct printing because it is printed directly on paper by printing plate

for the printing plate used in relief printing, in addition to the typesetting of the text part, others, such as special fonts or patterns, pictures, etc., use the photographic plate making method to make zinc plate (commonly known as electric plate), and recently developed to nylon offset plate to improve the point printing effect

generally, the letterpress printing plate is flat, but in some cases, the flat printing plate needs to be copied into a curved lead plate, which can be installed on the drum type rotary embossing machine for a large number of printing, such as newspapers

in addition to printing pictures and words, letterpress printing adds some accessories, and it can also print text patterns on concave convex printing surface, cut the printing surface (commonly known as beer sample), print pinhole lines for tearing paper, and print digital words with automatic transposition

flexgraph

rubber printing is similar to letterpress printing, except that the printing plate is a piece of soft glue, like the image glue used for stamping. The ink used is similar to gravure printing, with high volatility and thin, which is used for printing gummed paper and plastic bags

the method of plate making is divided into three steps: first, make the pictures and texts into an electric version for letterpress. 2、 A printing plate female mold that uses hard glue similar to bakelite to heat and press on the above electric plate to print hard blocks. 3、 Similarly, another kind of soft glue is heated and pressed on the female mold to produce the same offset plate as the original one in the laboratory environment in the first step

all kinds of adhesive paper, such as cellophane, P, V, C adhesive, polyester, acetate, etc., materials with no ink absorption and penetration on the surface can be printed on it. It is suitable for printing plastic bags, hand pumping and plastic packaging of large and small sizes. However, this printing method can't print fine dots and lines as well as offset printing and letterpress printing, so pictures should pay attention to emphasizing the big effect

planography

basic principle of lithography

lithography is named after the development of early lithography. In the early lithography, its plate material was used after grinding with stones, and then improved to metal zinc plate or aluminum plate, but its principle is unchanged

there is no difference between the printed part and the non printed part, that is, it is flat, and water and oil are not mixed. 5. In order to protect the human body, the printing part keeps a layer of greasy oil film, while the plate on the non printing part can absorb appropriate water. It is envisaged that after the ink on the plate, the printing part will repel water and absorb ink, while the non printing part will absorb water and form an anti inking effect, The method of printing by this method is called "lithography"

lithography developed from early lithography, because its plate making and printing has its unique personality, at the same time, it is extremely simple in work, and the cost is low, so it has been continuously studied and improved by experts in modern times, and has become the most used method in printing today

lithographic printing method

lithographic printing method is developed from the early lithographic printing transfer method, which is depicted on the transfer paper and then falls on the plate to become reverse grain, and then printed on the paper to become positive grain. Due to the pressure that this method bears during printing, the lithographic plate that is originally a flat plate (that is, the image part and the non image part are flat), after bearing the pressure, the ink occupying the plate will diffuse and expand, resulting in poor line drawing. Therefore, it was later improved to be called offset printing. Its printing method is to make the plate with low hardness of aluminum alloy material into normal lines, When printing, it is transferred on the rubber cylinder as reverse grain, and then printed from reverse grain to paper as normal grain, which can improve the elasticity of printing pressure

in the early stage, lithography was flat press type, and later developed into two types: flat round press type and round round press type. Most of the flat round press machines are used in special printing, such as proofing typewriters, etc. as for printing paper, all machines such as round press type are improved. Lithographic circular pressing is that the printing plate is placed horizontally, and the pressure part is a roller type pressing cylinder. This kind of printing method is very similar to the lithographic circular pressing machine in relief printing. Round plate round pressing is to wrap the printing plate on the drum, which is called the plate cylinder. The other drum on the machine is wrapped with rubber, which is called the rubber cylinder. The pressure part is also the drum type pressing cylinder. This machine with three basic drum structures is called the "offset printing machine"

advantages and disadvantages of lithography

① advantages: plate making is simple and low cost. The chromatic printing plate is accurate, and the printing plate is easy to copy. The printed matter is soft and soft. It can print in large quantities

② disadvantages: due to the influence of water glue during printing, the color reproduction power is reduced and the brightness is lack. The printing ink of the layout is thin (it can only show 70% of the capacity, so the offset light box poster must be printed on both sides to enhance its color). Special printing applications are limited

application scope

① posters, ② simple prices, ③ instructions, ④ newspapers, ⑤ packaging, ⑥ books, ⑦ magazines, ⑧ monthly calendars, ⑨ other related color printing and large quantities of printed materials

intaglioprinting

basic principle of intaglioprinting

there are many differences between the image part and the non image part, which is exactly the opposite to the relief plate, that is, the inked part of the printing plate has an obvious depression under the plate, while the non image part is glossy and smooth. When printing, it is necessary to roll the ink on the plate first, then the ink naturally falls into the concave image part, and then wipe the ink adhered to the surface (of course, the concave image ink will not be wiped off). After putting on the paper, use a larger pressure to imprint the sunken image ink on the paper. Anyone who uses this printing method is called "gravure printing"

intaglio printing method

intaglio printing method due to the heavy printing pressure, in addition to more actions than relief or lithography, special attention should also be paid to the pressure on the page. The printing method is the reverse of the page, and the printing paper is the positive grain

gravure printing is divided into engraving gravure and photogravure

① engraving gravure:

engraving gravure is an early evolution of engraving from metal decoration. At that time, engraved copper patterns were used as decorations, which was later used in printing performance

the copper plate printing paper used for engraving gravure was first wetted in the early stage, mainly to increase the adhesion of the common pair of inks, so the back of the paper needs to be covered with a thick cloth, and the ink adhered in the concave image can be pulled out and printed on the paper with greater pressure. The main disadvantage of this printing method is that it needs to be dried after printing, which will produce irregular expansion and contraction, resulting in uneven length of the printed products

but now copperplate printing has been improved to dry printing, which improves the flat arm of the layout, and makes the lines of engraving concave shallower. The ink adhered to it is easy to pull out. According to the depth of pattern and picture in copper plate printing and steel plate printing, the three-dimensional sense is expressed by the thickness and depth of lines. The printing plate with thick and deep lines has thicker ink, so the ink color is darker. The printing plate with thin and shallow lines has thinner ink, so the ink color is lighter. This kind of print is as wonderful as the design of modern visual art, but most of it is used to express patterns or words, while continuous tone like a photo is difficult to do

② photographic intaglio

photographic intaglio is also called photolithography, which uses the principle of photography to corrode the copper plate. It is a kind of adhesive tape (larbotissue) that has been photosensitively treated with potassium dichromate solution and a special screen for intaglio. After exposure, this kind of adhesive tape and the positive film of continuous version adjustment are printed. After two exposures, the adhesive tape can be developed by warm water. The black silver on the positive film of the adhesive tape in the light part of the picture is lighter, Then the adhesive tape is transmitted by light waves and hardened to a higher degree, so the adhesive film after water development is thicker, and the adhesive tape in the dark part of the picture is masked and expanded by the thick black silver of the positive film, so the adhesive tape can be transmitted by light waves and hardened to a lesser degree, so the adhesive film after water development is thinner. Therefore, this kind of developed adhesive tape with different thickness is pasted on the copper drum or flat drum and corroded by ferric chloride. Where the light part adhesive film is thick, the depth of the solution that can penetrate and erode the copper plate is relatively shallow, so the adhesive ink film is relatively thin, and the ink color printed is relatively light. Where the dark part adhesive film is thin, the adhesive thickness can be penetrated by the solution, and the etching into the copper plate must be relatively deep, so the ink film of the image adhesion is relatively thick, The ink color printed is darker

advantages and disadvantages of gravure printing

① advantages: ink expressiveness is about 90%, and there are rich colors. Strong color reproduction. Strong layout tolerance. The printing quantity is huge. The paper is widely used, and materials other than paper can also be printed

② disadvantages: plate making cost is expensive, printing cost is also expensive, plate making work is more complex, and a few volume prints are not suitable

application scope of gravure printing

engraving gravure printing is used in the printing of securities, such as banknotes, stocks, gift certificates, stamps, vouchers of commercial reputation or stationery, because its lines are exquisite and it is not easy to counterfeit. Because of its high cost of plate making and printing, few ordinary printed materials are used. As for photogravure, although its plate making process is more complex and its cost is also more expensive, it is not suitable for printing a small number of prints. It is generally used in a large number of printed materials, such as color magazines and the currently popular building materials printing, which are extremely suitable. Gravure printing adopts high-speed rotary type, which is not only fast, but also the ink film is much thicker than relief or lithography

stencilprinting

basic principle of stencil printing

in addition to the three formats of relief, lithography and intaglio, another kind of stencil printing similar to handicraft also accounts for a unique branch of modern printing industry. Due to the deep influence of modern business circles, it is also deeply valued in the design circles. Because of its unique expressiveness, hole printing has a wide range of applications. It is necessary for designers or ordinary people to understand some concepts. Where the image part is like a hole, and printed in this way, it is called "hole printing"

for example, generally, steel needles are used to engrave characters on wax paper or mimeograph printing with electronic etching, which is a more basic hole printing, while screen printing is applied in design or industry. In the early days, screen printing was used in handicrafts, and now it has developed into automatic printing. In plate making, photographic plate making methods have been used to form the layout; Because of its strong ink color and a special feeling, it is most suitable for special effects

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