And as far as environmental protection is concerned, screen printing is a heavy pollution process. First of all, its plate making process produces developing liquid, the use of ink produces ink barrels, cleaning up the cleaning waste water or waste rags. Oriental Longke Zheng Sen
1. What is called screen printing?
Screen printing belongs to the perforated printing, which is known as the four major printing methods together with lithography, letterpress and gravure. Perforated printing, including transcription, skeletonization, flower plate, spray and screen printing. The principle of perforated printing is: the printing plate (paper film plate or other plates made on the base of the ink can pass through the eyelets) in the printing, through a certain amount of pressure to make the ink through the eyelets of the perforated plate to transfer to the substrate (paper, ceramics, etc.) to form a picture or text. Transcription plate printing is the easiest type of perforated plate printing, which began in the late 19th century. This kind of printing is on special wax paper, made by typewriter or iron pen wax paper graphic plate, in the wax paper plate with an ink roller for printing, the substrate can be obtained on the desired printing effect. In perforated printing, the most widely used is screen printing.
Screen printing is a silk fabric, synthetic fiber fabric or metal screen taut on the frame, using hand-engraved varnish film or photochemical plate making method of screen printing plate. Modern screen printing technology, it is the use of light-sensitive materials through the photochemical platemaking method to produce screen printing plate (so that the screen printing plate on the graphic part of the screen holes for the through-hole, and the non-graphic part of the screen holes are blocked). Printing through the squeezing of the squeegee, so that the ink through the mesh of the graphic part of the transfer to the substrate, the formation of the same graphic as the original. Screen printing equipment is simple, easy to operate, printing, plate making simple and low cost, adaptable. Screen printing wide range of applications common prints are: color painting, posters, business cards, framed covers, commodity labels and printed textiles.
▼2. When was screen printing invented?
Screen printing originated in China more than 2,000 years ago. As early as in China's ancient Qin and Han Dynasties, the method of jiejie printing appeared. To the Eastern Han Dynasty clip Jie batik method has been generally popular, and the level of printed products has also improved. To the Sui dynasty during the daiye years, people began to use the frame with silk screen for printing, so that the folder jie printing process development for screen printing. According to historical records, the Tang Dynasty, the court wore fine clothing with this method of printing. To the Song Dynasty screen printing and development, and improve the original use of oil-based paint, began to add starch-based gum powder in the dye, making it a paste for screen printing, screen printing products to make the color more brilliant.
Screen printing is a major invention in China. The United States "screen printing" magazine on the Chinese screen printing technology has had this comment: "There is evidence that the Chinese in two thousand years ago, the use of horsehair and templates. Clothing in the early Ming Dynasty proves their competitive spirit and processing technology?quot; The invention of screen printing technology has promoted the development of human material civilization in the world. Today, two thousand years later, screen printing technology continues to develop and improve, has now become an indispensable part of human life.
▼3. What is the principle of screen printing?
Screen printing consists of five main elements, namely, the screen printing plate, the squeegee, the ink, the printing table and the substrate. The basic principle of screen printing is: the use of screen printing plate graphic part of the mesh through the ink, non-graphic part of the mesh opaque ink basic principles of printing. Printing in one end of the screen printing plate poured into the ink, with a scraping scraper in the ink on the screen printing plate to apply a certain amount of pressure, at the same time towards the other end of the screen printing plate to move. The ink is squeezed by the squeegee from the mesh of the graphic part to the substrate during the movement. Due to the viscous effect of the ink and make the impression fixed within a certain range, the printing process, the squeegee is always with the screen printing plate and the substrate line contact, contact line with the squeegee to move and move, due to the screen printing plate and the substrate to maintain a certain gap between the screen printing plate and the screen printing plate through its own tension and the production of the squeegee's reaction force, this reaction force is known as the rebound force. Due to the role of the rebound force, so that the screen printing plate and the substrate was only mobile line contact, while the other parts of the screen printing plate and the substrate for the detached state. Make the ink and screen fracture movement, to ensure the printing size accuracy and avoid rubbing dirty substrate. When the scraper scraped through the entire page after lifting, while the screen printing plate is also lifted, and the ink lightly scraped back to the initial position. This is one printing stroke.
▼4. What are the main differences between screen printing and other printing methods?
Screen printing and other printing methods compared to the main differences are as follows:
1) Printing adaptability flat printing, letterpress, gravure printing of the three major printing methods can only be in the plane of the substrate for printing. Screen printing can not only print on the plane, but also in the curved surface, spherical and concave-convex surface of the substrate for printing. On the other hand, screen printing can print not only on hard materials, but also on soft materials, regardless of the texture of the substrate. In addition, screen printing, in addition to direct printing, can also be used as needed to print indirect printing methods, that is, first screen printing on gelatin or silicone plate, and then transferred to the substrate. Therefore, it can be said that screen printing is very adaptable and has a wide range of applications.
② thick ink layer, three-dimensional sense of strong, rich texture Offset and letterpress ink layer thickness is generally 5 microns, gravure printing for about 12 microns, flexo (aniline) printing ink layer thickness of 10 microns, while the ink layer thickness of screen printing is far more than the thickness of the ink layer, generally up to about 30 microns. Specialized printed circuit boards with thick screen printing, ink layer thickness can be up to 1000 microns. Printed with foam ink Braille dot Yu, foam ink layer thickness of up to 300 microns. Screen printing ink layer thickness, print rich texture, three-dimensional sense of strong, which is not comparable to other printing methods. Screen printing can not only monochrome printing, but also for color and color printing plus network.
3 strong light resistance, bright colors due to screen printing has the characteristics of leakage printing, so it can use a variety of inks and coatings, not only can use slurry, adhesive and a variety of pigments, but also can be used to use the thicker particles of pigments. In addition, screen printing ink mixing method is simple, for example, can put the light-resistant pigment directly into the ink mixing, which is another major feature of screen printing. Screen printing products have the great advantage of high light resistance. Practice shows that, according to the use of black ink on coated paper after an embossing measured in the range of maximum density value for comparison, offset printing for 1.4, letterpress for 1.6, gravure for 1.8, while the maximum density value of screen printing range up to 2.0, so the screen printing products of the light-resistant than other kinds of printing products of the light-resistant, more suitable for advertising in the outdoor, signage use.
4 printing area of the current general offset printing, letterpress printing and other printing methods for the printing of the area size of the maximum size of the full-sheet size, more than the full-sheet size, it is subject to the limitations of mechanical equipment. And screen printing can be printed on a large area, today's screen printing products up to 3 meters × 4 meters, or even larger.
The above four points are screen printing and other printing differences, but also the characteristics and advantages of screen printing. Understand the characteristics of screen printing, in the selection of printing methods, you can take advantage of the shortcomings, highlighting the advantages of screen printing, in order to achieve more ideal printing results.
▼5. Screen printing is suitable for the performance of which types of originals?
Screen printing, like other printing, needs to accurately reproduce the graphics and color tones of the original. Screen printing used in principle and other printing methods used in the original manuscript is not very different, but in the specific plate making, printing practice, the requirements of the different places, which is mainly due to the characteristics of screen printing decided. In particular, due to the screen printing ink layer thick, bright colors, so in the selection of the original manuscript and plate to give full consideration to the special effects of screen printing.
In addition, screen printing with the original graphic lines, dot precision requirements and ordinary printing methods used in the original requirements are different. If the original lines, dots are very fine, screen printing plate is a very difficult thing. Therefore, screen printing technology is not suitable for reproducing fine lines, dots of the original. In the selection of printing methods to fully consider the characteristics of various printing. Even in the screen printing plate should also pay attention to the selection of the appropriate mesh, in order to achieve the full reproduction of the purpose of the original.
Screen printing is more suitable for the performance of text and lines of bright monochrome into the color set of the original, also suitable for the performance of greater contrast, clear levels of color originals. Through the special effects of screen printing, making reproductions have a rich expressive power, through the rich and thick ink layer and the tone of the contrast between light and dark, fully express the texture of the original content and three-dimensional effect.
Screen printing photographic plate original reflective original and transmissive original two, usually mainly use reflective original. Most of the color photographs use transmissive originals.
Screen printing is mainly used in the production of positive images of the screen. Different methods of plate making also have different requirements for the original.
▼6. What are the main features of screen printing?
The characteristics of screen printing are summarized in the following aspects:
①Screen printing can use many types of ink. That is: oil-based, water-based, synthetic resin emulsion type, powder and other types of ink.
② soft layout. Screen printing layout soft and flexible not only for printing on paper and fabric and other soft items, but also suitable for printing on hard items, such as: glass, ceramics, etc..
3 screen printing pressure is small. Since the pressure used in printing is small, it is also suitable for printing on fragile shopping bodies.
④The ink layer is thick and has strong covering power.
5 is not subject to the limitations of the shape of the surface of the substrate and the limitations of the size of the area. As can be seen from the foregoing, screen printing can be printed not only on the plane, but also on curved surfaces or spherical surfaces; it is not only suitable for printing on small objects, but also suitable for printing on larger objects. This printing method has great flexibility and wide applicability.
▼7. How many screen printing methods are there?
There are usually two types of screen printing, namely, manual printing and mechanical printing.
Manual printing refers to the renewal of the paper to the receipt of the paper, the printing plate up and down to move, scraping the scraper scraping are manually operated.
Mechanical printing means that the printing process is completed by mechanical action. Which is divided into semi-automatic and fully automatic printing, semi-automatic means that the substrate into and out of manual operation, printing by mechanical completion; fully automatic means that the entire printing process is completed by machinery.
▼8. How is screen printing categorized?
Screen printing is not only adapted to general paper printing, but also adapted to a very wide range. For example: ceramics, glass, printed circuit boards and so on. According to the texture of the substrate is different, the printing is not the same, although there is an inextricable link between the various series, but because the substrate is different (i.e., different chemical and physical properties), each has its own specificity. So usually people according to different substrates are divided into: paper printing, plastic printing, ceramic printing, glass printing, circuit board printing, metal printing, textile printing and other major categories. This has formed their own relatively independent printing system.
▼9. What are the main applications of screen printing?
The range of screen printing applications is very wide. In addition to water and air (including other liquids and gases), any kind of object can be used as a substrate. Someone evaluating screen printing has said this: if you want to find the ideal printing method on earth for printing purposes, it is likely to be the screen printing method.
Specifically screen printing is mainly used in the following areas:
①Paper Printing
Fine Art Printing - advertisements, drawings and magazines, calendars, lanterns paper, etc..
Trademark Printing
Transfer Printing
Packaging Printing
Building Materials Printing - paste wallpaper and so on.
②Plastic Printing
Plastic soft sheet - vinyl toys, school bags, plastic bags, etc..
Plastic markers - fake metal composite materials and a variety of markers.
Production parts - instrument parts.
③Wood products printing
Crafts - lacquer ware, wooden crafts, toys.
Processing semi-finished products - sporting goods, wood panels, ceilings, road signs, signboards, fake metal wrenches, billboards, etc.
④Metal products printing
Metal cylinders, metal utensils, metal products.
⑤Glass and Ceramic Products Printing
Glass - mirrors, glass panels, cups, bottles, etc.
Ceramics - utensils, handicrafts.
6 Signage
Text description boards, dials, molded items.
7 Circuit Board Printing
Printed circuit boards, substrates for civil or industrial use, thick film integrated circuit boards.
8 Printing and Dyeing
Printing and dyeing - flags, cloth, towels, handkerchiefs, shirts, undershirts, knitwear, and so on. '
Other printing - pockets, shoes, number cloths, and all kinds of bags, backpacks, carry bags, school bags, etc.
9 leather products printing
▼10. What is the main process of screen printing? Its process flow is the needle?
The main process of screen printing is: making the original, making the screen printing plate, printing, ink drying and so on.
▼11. What is a tensiometer?
Tensiometer is an instrument that measures the amount of mutual traction between the screen and the fixed screen contact body when the screen is subjected to tension. Tensiometer has a mechanical and electronic two kinds, the unit of measurement of tension expressed in newtons / cm. Tension can also be expressed as a relative value. Centimeter tensiometer is a relative value to express tension, is through the tensiometer's own weight to make the depth of the silk screen sinking value (mm) to calculate, the tension value can be obtained directly from the indication plate, or indirectly from the control panel. Tensiometer has manual operation and mechanical operation of two kinds. Tensiometer is an important testing instrument to check the quality of screen printing plate. In order to ensure that the plate requirements of the tension, in the process of taut net or taut net after the use of tension meter measurement.
▼12. What is a mesh gauge? What is its use?
Mesh ruler is also known as warp and weft density meter. Mainly used to measure the mesh of various screens. Mesh ruler has a glass plate type and plastic sheet type two. The measurement method is: measurement, first of all, make the screen in the state of translucent or placed on the plate table, the mesh ruler on the screen, and then the mesh ruler in the screen slowly moving, so that the vertical line on the mesh ruler and the screen parallel to the warp or weft, then due to the screen warp and weft lines and the mesh ruler on the vertical line to produce overlap effect, the formation of prismatic pattern on the mesh ruler, the pattern of the transverse diagonal pointed to the mesh ruler on the corresponding The corresponding scale number on the mesh scale pointed to by the horizontal diagonal of the pattern is the mesh number (inches or centimeters) of the screen measured.
The mesh scale is a common tool for measuring the mesh of the screen, usually to maintain the precision of the measuring instrument, the accuracy of the measurement data, we must keep the mesh scale clean, to prevent scratches and bruises on the mesh scale, the instrument should be wiped clean after use, properly stored.
▼13. What is a densitometer? What is the use of density meter?
The densitometer is a common instrument used by printers to measure originals. Is the measurement of black and white original gray value and measurement of continuous tone or dot value of the photoelectric measuring instrument. Densitometer is divided into transmission densitometer and reflection densitometer two kinds. Transmission densitometer is suitable for measuring the transparent original, reflective densitometer is suitable for measuring the field original. Densitometer measurement range is 0-2.5, the larger the number, the higher the blackness. The basic principle of measurement is to measure the degree of blackening of the photographic material after exposure and development, i.e. blackness. In plate making, the photographic material on the silver bromide, by the action of light, after the development of the reduction into metallic silver, the formation of a certain degree of light resistance. Blackness is large, high density; blackness is small, low density. Measuring meter with a filter, you can also measure the color density of color originals. The principle of measurement is similar to the above basic principles.
▼14. What is a colorimeter? What is its use?
A colorimeter is also called a colorimeter. It is an instrument that measures the color characteristics of a material. The main purpose of the colorimeter is to measure and analyze the color, hue and color value of the measured material. If the colorimeter and computer connected to the machine, you can improve the analysis of color and processing capacity, and users can find from the microcomputer's color storage library to transfer a variety of data for color matching.
▼15. What is a hardness tester? What is its use?
Hardness tester is the instrument to measure the hardness of the object, according to the degree of complexity can be divided into simple hardness measurement and complex hardness measurement of two kinds of testers. Hardness tester is widely used, commonly used in the rubber industry, in the screen printing process, the hardness tester is mainly used to test the hardness of the squeegee material.
Edit this paragraph Aluminum signage classification 1. screen printing aluminum oxide color signage aluminum plane anodic oxidation signage is also a signage, it is more widely used. It is characterized by high brightness, high hardness and good abrasion resistance. The traditional production process is roughly as follows: mechanical polishing, chemical polishing, oxidation; indirect plate making screen plate, zinc barium white thick paint plus alkyd varnish for protection printing, so that whether it is screen plate making or dyeing, there are many processes, materials, low print resistance, high cost shortcomings. Today, we adopt the latest technology to use non-toxic nitrogen-based photopolymer to make plates directly, so that we can achieve the requirements of fast plate making, high resolution, high print resistance and low material consumption. Can also print paint, dyeing, printing materials back to the process of unity, the use of homemade water-based dyeing materials, direct dyeing, successive sets of colors. This can greatly simplify the entire process and operating procedures, so that the plane oxidation dyeing signs have a new process.2. High-gloss three-dimensional embossed aluminum signs with the continuous improvement of production technology, people's material and spiritual life is increasingly demanding. People not only have higher and higher functional requirements for products, but also for the appearance of the product modeling, decorative requirements are also higher and higher. Especially with the continuous expansion of foreign trade market, in order to improve the competitiveness of products in the market, high-grade products of high-gloss three-dimensional embossed signs have been widely used.3. Screen printing plating plaque plaque is one of the main products of the sign factory, mainly used for the company's corporate signage. Plaque material is mainly metal-based, it requires solemn, highlighting the image, decorative. Traditional metal plaques are mainly square plaques with brass ground, corroded characters and black lacquer injection. But as people's aesthetic views continue to change, the gradual development of the commodity economy, the quality of the plaque and the appearance of the shape also has new requirements. The introduction of screen printing processing technology in the plaque industry not only promotes the development of screen printing technology, but also provides technical support for the development of new products in the plaque industry. Screen plating plaque is the combination of signage plating and screen printing process under the product. Screen printing plating plaque is the basic method: in the copper plate first screen printing technology system plain text graphics, ink layer to protect the non-graphic part, and then in the graphic part of the copper, nickel, chromium plating, and finally mechanical shaping, protection processing and become. 4. Screen printing conical dial screen printing conical dial method: first screen printing screen printing to the graphic to the transfer of the rubber above, and then mounted on the fixture of the conical parts, and then rolled over the transfer of the rubber, and then rolled over the conical parts, and then rolled over the transfer of the rubber, and then rolled over the conical parts, and then rolled over the conical parts, and then rolled over the conical parts, and then printed on the transfer of the rubber. Transfer rubber rolled over, so that the graphics can be printed to the surface of the conical parts. 5. imitation porcelain oxidation sign imitation porcelain anodic oxidation sign surface is enamel-like, soft color, has a good resistance, high hardness, you wear resistance, good insulation, insulation and other advantages, is a good instrumentation decorations. The production process will have pollution exhaust gas discharge, so the equipment must have air extraction and ventilation equipment to avoid poisoning. Imitation of porcelain signs surface treatment and silkscreen sandblasting oxidation embedded paint signs are roughly the same, but do not need to enter the chemical polishing, can be directly oxidized. Imitation of porcelain oxidation dyeing signage process and screen printing aluminum oxide color signage is no different.6. Screen printing aluminum oxide signage aluminum oxide signage, panel after oxidation, the surface will be attached to a layer of oxide film, is the surface is hard and smooth. With ordinary screen printing ink adhesion is poor, this is the most important problem. To solve this problem, we must first solve the screen printing ink and operation problems. Aluminum oxide screen printing ink must be used, which is the key to the success of screen printing aluminum oxide signs. The difference between this kind of ink and general ink is that it will be firmly adhered to the surface of the aluminum plate, and has a very good light resistance, which is the most ideal ink screen printing aluminum signage.7. Screen printing corrosion signage corrosion signage belongs to the traditional signage, common sandblasted oxidation paint filler signs, such as: license plates of vehicles and ships, equipment number, various machine tools and electrical appliances nameplates; operating environment of the harsh electromechanical products, copper-plated frontal signage; For instrumentation, electronic equipment surface decoration of porcelain oxidation paint signs and high-gloss signs and so on. These signs on the graphics in the past are through the liquid photopolymer through the photochemical effect of the realization. This method exists in the production process, production efficiency, labor intensity and other shortcomings. Second screen printing processing technology printing graphics, greatly improving production efficiency, and can save a lot of raw materials.8. Screen printing convex-concave color aluminum signage convex-concave signage is characterized by paint in the concave, good resistance to abrasion, but also has a three-dimensional effect, generally used for mechanical nameplates and company plaques, etc.. The traditional production method is manually in the corrosion of the concave tracing paint, and then manually trimmed to remove the edge of the residual paint this method is not only time-consuming, inefficient, requiring operators to be very skilled outside, and the production of the sign out of the word change is not clear, the quality is not stable. Only suitable for the production of a number of small batches, the number of colors, low quality requirements of the simple signage. The use of screen printing technology, there will be no such problems. 9. screen printing sandblasted oxidized embedded paint aluminum signage screen printing sandblasted oxidized embedded paint signage process, is a traditional signage production process. The appearance of these products is silver-white, high surface hardness, good abrasion resistance.10. Silkscreen water-white oxidized aluminum signage water-white oxidized aluminum signage is a new type of matte surface signage appeared in recent years in China. This kind of signage appearance is milky white, smooth surface, with resistance to humidity and heat, salt spray, mold resistance performance, but also has a very strong resistance to sunlight, abrasion resistance, resistance to organic solubility, applicable to the need for frequent wiping of the machine tool and the work in the environment of the more adverse conditions of the whole machine. The most important thing is wanton water white aluminum oxide signage process is less, high process, basically no three wastes.