The latest progress of screen printing in the field of plastic decoration

Xin Zhong Plastic Packing Machinery Co., Ltd.

The latest progress of screen printing in the field of plastic decoration
Foreword
Plastic products have entered the commercial market long ago. At present, the decoration of plastic products mainly adopts screen printing, and the cooperation between screen printing and plastic decoration industry has made continuous progress. As plastic processing plants continue to develop new material formulations, screen printing has been able to print on plastics with different surface textures, different hardnesses, and different beginnings. So far, screen printing has surpassed other alternative processes for plastic decoration such as flexographic printing, offset printing, pad printing, and digital printing. However, with the continuous progress of these printing processes, the plastics processing industry naturally raises the question whether screen printing can continue to occupy the dominant position in the field of plastic decoration.
Of course, we expect that the demand for the plastic decoration market will continue to expand with the emergence of new plastic products. The rapid development of IMD is a good example of the main role of screen printing in the plastic decorative market.
Screen printing can be called universal printing. It can use a variety of inks to print on a variety of substrates. It is this flexibility and versatility that facilitates it in many different printing processes. Take advantage of. And the most important is that it has high productivity, predictability, and consistency in printing.
This article will discuss screen printing equipment, inks, screens, and process features, and look forward to some new advances in this area to further improve screen printing quality.
Ink No other printing process can use as many kinds of inks and coatings as screen printing. Other printing processes are often limited to print on plain paper, cardboard, and plastic, and the ink layer is relatively thin. The thickness of the screen printing ink layer can be flexibly controlled according to the needs, thin or thick; substrates include various materials: small wood, textiles, metal, glass, ceramics and so on.
At present, there are many types of screen printing inks, such as fluorescent inks, fragrance inks, color-changing inks, reflection inks, foaming inks, and discharge inks. Different substrates require different formulations of inks and can be selected from matt, semi-gloss, high gloss, and clear inks.
In addition to printing on flat plastic materials, screen printing can also be directly printed on containers, bottles and other cylindrical objects. In addition, screen printing inks do not have excellent fade resistance, weather resistance and wear resistance. Rubbing.
In order to meet the environmental requirements of inks, screen-printing ink manufacturers have also invested a lot of money in research to develop many environmentally-friendly products such as UV inks, water-based UV inks, and water-based inks, and also developed instrument plastics that meet health standards. Box decorative ink.
Wire Mesh Wire mesh plays a decisive role in the quality of the image or ink layer. Screen is the central link of the entire screen printing technology. At present, there are various types of screens on the market, such as metal screens and synthetic fiber screens, which are suitable for printing different products. But what is important is that screen printers or plastic decorators must have a good understanding of the variety of screens and screens for each type of print. Grasping the knowledge of the screen can avoid unnecessary interference in the printing, and can ensure the economic use of ink. The correct choice of screen has a great influence on the final printing effect. The following points should be noted when selecting the screen.
The larger the opening of the screen, the greater the ink flow through, and the thickness, flatness, ink drying, ink consumption, and hiding power of the ink layer are largely determined by the screen.
The screen must be selected according to the substrate used (paper, cardboard, plastic, and the smoothness or roughness of the surface, etc.).
High-precision prints require the use of screens with excellent stability, such as wire mesh or polyester mesh.
The right choice of screen to use directly affects the cost of the product.
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Xin Zhong Plastic Packing Machinery Co., Ltd.

Coating Compared with other printing processes, the screen printing ink layer is relatively thick, and it can also flexibly control the ink layer thickness according to the requirements of the substrate. For example, most images are printed with a dry ink film thickness of 5-7 UM, and can be increased to 100 UM when needed. This is very important in electronic printing such as circuit boards and film openings.
It is clear why people often say that screen printing not only represents the printing process but also coating technology. At present, the application of screen printing technology is becoming more and more extensive. At the same time, the doors of many new industrial fields are open at all times, creating more opportunities for screen printing.
Printing format The printing format can range from a few centimeters to several meters. In super-large-format advertising printing, the substrate can be not only vinyl paper but also rigid plastic.
Special effects and shapes Screen printing is economical for both long-lived and short-lived jobs. Offset printing, flexo printing, and stamping are all only cost-effective for medium-to-long live printing. Digital printing is only It is only worthwhile to print in the short version and in the middle version. Compared with screen printing, there is a great deal of flexibility.
Durability Chemical resistance and weather resistance tests have shown that screen printing inks have a longer life than other printing inks. This is very important for the printing of traffic signs and sports equipment (table skis, etc.), because these prints must be Experience the challenges of harsh weather conditions.
The following will introduce some of the latest advances in screen printing technology. Screen printing has now entered a higher stage of control, becoming a predictable, repeatable process.
Meet Predictability Requirements In the prepress and printing process, the focus is mainly on how to increase efficiency and achieve consistent printing results.
In order to be able to operate successfully under a variety of conditions, the key is to develop a reasonable work routine, simple steps, and testing of intermediate results. Only in this way, those semi-skilled operators can fully understand every working procedure and timely and systematically remedy the mistakes.
Simplify the prepress program Most screen printers use flat printing methods. To improve the quality of printing, the work procedures must be simplified, and equipment and materials must be improved. At the same time, the screen tension, screen mesh number, etc. must be systematically Testing.
In recent years, there have been more and more manufacturers adopting rotary screen printing methods. A new development is the use of photosensitive screen printing plates. This printing process is much simpler than plastic threads.
The positioning system positioning system is very important in the prepress program, which can ensure the accurate positioning of the image on the screen. The positioning mark can be directly marked on the printing plate or the film, or it can be automatically used on the printing machine by using the prepositioning system. The screen is accurately positioned to ensure greater accuracy and can be replaced in a short period of time.
Wire Mesh The wire mesh is the core carrier of the printing plate. The prepared stencil will transfer the ink to the substrate through the mesh under the pressure of the squeegee. During operation, it is very important that the screen maintain a high and stable tension. A new generation of high-strength polyester screens can meet this quality requirement, higher screen tensions than in the past, longer retention times, more precise printing, and higher print rates.
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Xin Zhong Plastic Packing Machinery Co., Ltd.
Photosensitive resin plates For super large-format printing, high-sensitivity resin plates have been developed and these advances are beneficial to the production of standard stencil emulsions.
The coated plate can be stored for a longer period of time. The pre-coated screen version (PCF) has also been developed and can be used for circuit board printing and CD/DVD printing, which can reduce a large number of manual operations, improve printing quality, and reduce production costs. Pre-coated screens can be automatically stretched and glued and quickly exposed.
Excellent printing performance Most screen printing can be combined with high-speed production lines, and its production speed is limited by many factors, including the drying box's traffic, the substrate's automatic feed speed and so on. Screen printing can usually be combined with other printing processes as a local coating method, and this combination can produce higher value.
Another development is that the squeegee uses two parallel rows of metal comb-like structures to ensure that the squeegee blades do not bend and deform, thus keeping the squeegee angle constant. Even in line or screen printing, it can ensure that the ink passes through each mesh, has extremely high printing accuracy, printability and consistent printing effect. At the same time, it reduces the friction of the stencil and reduces the printing pressure.
Ink Progress At present, the types of ink raw materials are increasing, and the quality of ink is greatly improved. Today's UV inks already meet high quality printing requirements, including good ink flow, fast cure, and good adhesion to substrates. At the same time, since the UV ink contains no solvent, and the use of computer ink distribution, ink waste and environmental pollution are greatly reduced.
Printing equipment The goal of modern screen printing equipment is to make the process flow more reasonable. It not only pays special attention to the printing operation, but also pays more attention to the replacement speed of the job. The operator only needs to make fine adjustments to complete the basic adjustment before starting the machine.
Online Production There are usually several different printing processes in an online production line and can be converted in a matter of minutes, for example, from screen printing to flexo printing, which results in higher productivity and greater flexibility. It is very important in label printing.
Drying System Recent UV drying equipment has made significant progress, high curing speed, safety and reliability. For synthetic material prints, temperature and temperature control are particularly important, while small size is another major feature of the new UV drying equipment.
Conclusion Until recently, some people realized that screen printing could be used as a major process for advertising, signage, point-of-sale advertising, and other areas. Screen printing has very distinct characteristics. Its versatility and progress in technology have a strong appeal in many fields. However, it is estimated that more than 60% of the world's screen printing market needs to simplify the production process, enhance the consistency of printing and the ability to print repeatedly. Many screen-printing companies are actively responding to these requests and have found solutions that are beneficial to all companies.
For example, pre-coated screen printing is an example of simplifying the plate making process first in the field of circuit board printing, and it is also proved that it is also suitable for CD/DVD printing. Another example is the production of recreational sports equipment, decorative inks for sleds, surfboards, and windsurfing, etc.