1. How to choose screen printing platform and screen printer?
A: The manual screen printing platform includes simple stamp pad, light pad pad, suction pad pad and multi-color wheel transfer pad. It is suitable for screen printing plates, panels and labels. Each of them has different characteristics and should be selected according to specific needs, but the common requirement is high repeatability to facilitate accurate multi-color overprinting. In the printing of large-area, large-area hollow printing, large-area multicolor printing, manual screen printing platform is difficult to control the quality, then you need a flat screen printing machine to solve. The pressure of the screen printing machine is the same after adjustment, and it is stronger than manual screen printing. Therefore, screen printing plates, panels, screen printing platforms and screen printing machines should be equipped to meet different needs.
2. How to control the screen size of screen printing plates and panels?
A: There are no screens, screens, and labels on the screen. The network is too big to fit. Generally, the tension of the screen is large, and the distance from the screen is the best. This squeegee is line contact and can bounce in time. The general rule is that the microprinting plate printing plate pitch is 0.5 ~ 1mm, the small screen printing plate spacing is 2 ~ 3mm, the medium screen version of the network spacing is 3 ~ 5mm, large screen printing plate (such as 1m × 0.8m) The net distance is 5~7mm.
3. What are the commonly used positioning methods for manual screen printing?
A: There are 6 commonly used positioning methods for manual screen printing:
1. Corner positioning: suitable for good print size consistency;
2. Hole location: suitable for thicker printed materials, such as circuit boards;
3. Three-point positioning: Feeding should be light and the best vacuum adsorption is appropriate;
4. Positioning of the crosshair: divide the transparent and opaque materials into two types. First, print once and mark the crosshairs before overprinting.
5. Graphic positioning: mainly overprint on the 4-color rotary screen printing platform, place the film on a worktable, and then align the four screens respectively with the film, and fix it afterwards;
6. Tooling positioning: It is mainly used for the positioning of injection molding panels. The position of the semi-automatic screen printing machine is to attach a protective film on the printed part, test it and adjust it (adjusting the front, rear, left and right), and lock it after adjustment. The automatic screen printing machine is automatically transmitted, positioning the front block, left and right block and suction cup with positioning, screen printing and then sent to the next process.
4. How to adjust screen printing ink?
Answer: When the ink is used, it is necessary to adjust the thinning and drying speed, and evenly stir it evenly, and eliminate air bubbles, such as adding thinner, defoaming agent, drying oil, etc., and adjust it before use.
5. How to check the ink selection is correct?
A: After the ink is adjusted, try the printing. If the printing is not a paste, it is a net blocking, or the combination is not strong after printing, you should consider replacing the ink and reselecting the ink.
6. What should I pay attention to when printing screens and panels?
Answer: 1. Ink can not be scraped to the border, some graphics can be, or the ink will go to the frame, which makes it dirty.
2. The ink is either returned completely, or it is not returned to ink, and it cannot be returned to a part of it. Otherwise, the inconsistent printing ink thickness results in inconsistent color.
3. Hand-scraping, scraping angle can not be large before the small, the angle is inconsistent, otherwise the amount of ink under the squeeze is different, the thickness of the line is also different.
4. The speed of hand-scraping must not be negligible, slow, or paused. It is required to be uniform so that the screen can be rebounded in time.
5. The squeegee pressure cannot be suddenly changed, and the squeegee must have the same force.
6. The manual printing is the basis of machine printing. With the manual printing of the mind-sensing adjustment machine, it is known.
7. The cleanup requirements are clean and neat, and attention is paid to summarizing the tips. Ink cleaning machines are now available, and recycling measures are in place to protect the environment and protect the health of workers.
7. What are the requirements for screen printing and panel scraper?
Answer: The scraper is required to be pointed, flat, hard, elastic, non-notch, and solvent-resistant. The tip is required to print clearly; the squeegee is to be inspected with a glass plate to see if it is even. If it is uneven, it must be ground with a screed; the hardness of the squeegee is usually 70°. The medium hardness is required; the elasticity is required to avoid slight Injustice is not good, and there must be no gaps on the blades; solvent resistance is also required so that the blades are not easily damaged.
8. What are the advantages and disadvantages of the light and solid inks, thermosetting inks, volatile inks, two-component reactive inks, and water-based inks selected for screen printing?
A: Volatile drying inks are mostly used in plastic products, and they are prone to clogging. The organic solvents also pollute the air. They should use other inks instead. Thermosetting ink is not easy to block the network is conducive to operation, but it consumes a lot of heat. Light-curable inks dry quickly, do not block the net, are advantageous to operation, have many advantages, and are used more and more. The two-liquid reaction type ink has the advantages of strong adhesion, and is not easy to block the network, and is dried and cured by chemical reaction, which is also advantageous for operation and use. The disadvantage is that it must be used within a specified period of time after adjustments have been made. Otherwise, it cannot be used, and it is prone to waste. Water-based ink is the development direction, no pollution, and good environmental protection.
9. What are the types of signage panels?
A: There are about 20 kinds of common signage panels from the process, as follows: (1) film dyeing and ink marking; (2) etching aluminum, copper, stainless steel, titanium gold signs; (3) screen printing and plating, Electroformed combination of gold medals; (4) aluminum oxide coloring and combination of process signs; (5) offset metal panels; (6) screen printing metal and resin panel sign panels; (7) hot stamping signs; (8) printing signs (9) Embossed high-gloss cutting label; (10) Disu(Crystal plastic) sign; (11) Plastic electroplating sign; (12) Two-color plastic injection sign; (13) Computerized lettering sticker label; (14) Computer Engraving Signs; (15) Inkjet Print Sublimation Transfer Panels and Medals; (16) Screen Printing Fluorescent, Luminous, Reflective Signs; (17) EL Luminous Signage; (18) IMD Screen Printing, Embossing, Injection Molding, Mobile Phone Panels (19) offset printing, resin printing, screen printing stickers; (20) offset printing, screen printing magnetic cards, VIP cards and so on.
10. What are the advantages and disadvantages of electrolytic etching?
A: The commercially available electrolytic etching machines are all hand-spray type, and all use salt water as the etching solution. There are two types of power, the advantages are no pollution, easy operation, suitable for small-scale production, small area etching, It is convenient to remove the titanium layer. The disadvantage is that it cannot be mass-produced, nor can it be used for etching large areas of embossed letters. Equipment manufacturers are still improving, such as the type of power supply, electrolyte formulation, equipment structure, etc. are improving in order to improve the quality of etching and solve the deficiencies. Users can use both electrolytic etching and chemical etching to achieve their respective advantages.
11. How is electric coloring?
A: In the past, the coloring of etching signs was solved by painting and lacquer. The new process used cathodic electrophoretic paint instead of painting and filling paints. The method is similar to electroplating in that the workpiece is hung on the cathode and the electrophoretic paint is deposited on the workpiece after the power is applied. The process conditions are controlled, the pigment is cleaned and dried after the coloring, and then the protective layer is removed with alkaline water. The electrophoretic paint on the figure is not affected by Influence, if it is made of bronze medals, it should also be coated with a protective varnish. This method is now used in the production of copper plate paintings and the production of stainless steel signs. Qingdao Sifang Brothers Screen Printing Co., Ltd. has special equipment and special electric coloring liquid (developed by oneself), and users respond well.
12. What is a gold medal?
A: A gold medal is a new process that uses the combination of screen printing, electroplating, and electroforming to make signs. It replaces etching, painting, filling, and electrophoretic paints in etching signs. The method is to use screen printing to print each color block on a copper plate or a stainless steel plate. The ink must have good bonding strength and resist electroplating. Uncovered are all thin lines. This small area of ​​metal underlay is thickened with electroplated nickel and then plated with gold to become a gold medal. This kind of sign is rarely seen in the market. Most of them are on glossy stainless steel plates or brushed stainless steel plates. Screen printing is a large-scale photoimprinting and anti-corrosion plating ink. Then the negative plate is used for printing and developing. And lace, the uncovered small area metal bottom layer is treated with thick nickel plating and surface gold plating to make a gold medal, and then the protective layer is removed with fire alkali to reveal the gold hollow edge and lace and a large area of ​​stainless steel bottom layer Only the hollow words can be manually filled with paint, and the brand made is very popular. From the above, it can be seen that the production of such gold medals requires screen printing technology and electroplating technology, and the selection of anti-corrosion and electroplating inks is required so that gold medals can be piled up.
13. How do inkjet printing sublimation panels and medals are made?
A: This is also a brand new process, suitable for making small batches of various types of panels and medals. The production method is: There is a ready-made aluminum plate with good surface treatment and varnish coating, which can be cut and shaped according to own needs. Then use the computer to design the color graphics and image text. After the layout is finished, use a color inkjet printer to output the reverse drawing. The color ink must be a special sublimation ink. The paper sample is pressed on the above aluminum plate, and a certain temperature, pressure and time are controlled by a hot press machine to transfer the colored text, graphics and images on the paper pattern to a metal plate to make a panel or a medallion of a positive figure. The medals are even more beautiful with the specially made cards. The disadvantage of this technique is that they are more expensive.
14. What are the uses of computer lettering stickers in sign making?
A: The computerized lettering stickers (sticky stickers) are often affixed to titanium plates, porcelain white organic plates, and glass mirrors for signs, showing gold, white or mirror characters. They are beautiful and generous, and can also be reposted on aluminum profiles. The signs and guide plates are made on the seat and the card holder, which is convenient and beautiful. Computer lettering is also widely used in the production of light boxes, plaques, banners, and panels.
15. What is the use of computer engraving in sign making?
A: The computer engraving sign is also a new process, it has a strong three-dimensional, especially the three-dimensional engraving card is more beautiful. Frequently used are two-color plate engraving signs and panels and plexiglass three-dimensional engraving cards. There are laser engraving marks and cutting metal plates, plastic plate text graphic signs, the effect is very good.
16. What are the common platemaking methods for screen printing plate?
Answer: There are two commonly used platemaking methods: First, the direct method, diazo photosensitive plate; second is the indirect method, photosensitive film plate making, especially the use of capillary photosensitive film plate, the quality is very good. Diazo sensitized plate making is easy to learn, and the printing rate is also high; photosensitive plate making requires skill and skill.
17. Why do I have to use film negatives to make small, thin lines?
A: The transparent part of the film is transparent and the dark part is very dark, which is conducive to making the plate and minimizing the time of printing. Such as sulphuric acid paper or paper oil-coated negative plate, such as semi-transparent plastic film sun, thin lines due to the diffraction of light also solidified, it is difficult to develop.
18. What are the specifications of the capillary photosensitive diaphragm and where can it be sold?
A: The British autotype company's products have thickness of 18μm, 25μm, 35μm several specifications, suitable for the production of signage panel screen printing version. It can be purchased at Sanhe’s sales offices in Beijing, Shenzhen, and Shijiazhuang.
