Electronics Engineers use the terms screen printing, screen printing and silk-screen legend, which indicates in writing to the PCB. Silk screening is much more convenient and flexible than other traditional printing methods. For one thing, need not appear on the surface, under pressure, unlike etching or lithography, and need not be flat. Screen printing inks can work in several areas – such as ceramic textiles, metal, wood, paper, glass and plastic. As a result, screen printing is used in various industries, from clothing to product labels for printing PCB.
Silk screen printing technology is quite simple and requires no great skill. The screen is made from a piece of porous, fine fabrics – originally silk, but now is made of polyester or nylon – stretched over a wooden or aluminum frame. Areas of the screen is blocked non-porous standard, which is negative and printed image. In other words, open spaces are where the ink will appear. The screen is mounted on a piece of dry paper or fabric. Ink is placed on the screen and a squeegee or rubber blade used to push the ink evenly across the screen openings and onto the substrate. The ink passes through the open space on the screen onto paper or fabric, and then placed under the screen is removed. The screen can be reused after cleaning.
electronic printed circuit board industry is evolving fairly rapidly, as new cost-effective production technology became available. Direct digital printing is the usurping the traditional photolithography and screen printing processes, which are excluded from the PCB industry for the past two decades. Direct digital printing with individual PCB, used just before assembling them. The obvious goal is to print a unique mark on each vessel, which can later be used for the determination of the Board. The mark must be permanent and usually contain inerasable and 1D or 2D machine readable code, with alpha digits.
Manufacturers say big 1000000 PCB boards and more than a year the use of heat-cured printing ink to print legends that cover each side of the boat. In this way, digital printing can not print the whole party on board, at a price that is competitive to screen printing. Several other options are available to distinguish the Label Preprinted Continuous application of solvent-based Digital Ink Jet Printing Ink Laser radical patches, etc.
Preprinted Label Application: People who produce small quantities of PCB started and hand-printed labels for office equipment applied to each PCB, either before or after assembly. But if production levels increased, reliability and cost of implementing the owner’s signals is a problem. Automated systems for print and apply labels are also available. Disability is these systems need to place labels very carefully because of PCB space constraints.
Solvent Based Continuous Ink Jet Digital Printing: This technology has been adapted to mark a variety of industrial products including PCB. These systems are a constant flow of ink to a desired position using electromagnetic fields. While solvent-based inks produce permanent marks porous surfaces can not be a permanent non-porous surfaces.
Many industries are now using lasers to engrave marks on a wide range of industrial components. Lasers have been used to engrave marks onto boards with limited success due to lack of contrast resulted in character. Some further tests to overcome, and one of them is that the ink patches printed circuit boards.