The hottest screen printing and high-tech film swi

Silk printing and high-tech film switch manufacturing technology

I. application of film switch in high-tech field

film switch takes silk printing as the main process means, and is one of the few independent products that can serve silk printing in high-tech field

membrane switch has the decorative and marking functions of traditional panel; In addition to the switching and manipulation functions of switching elements, membrane switches also have the functions of connecting switching elements with the host circuit, including switch wiring and outgoing line (i.e. switch circuit), and have the functions of reading display transparent window and indicator light transparent window. Therefore, membrane switches are neither a single new panel nor a single switching element, and they are a kind of novel electronic devices that integrate functions and decoration

due to its simple structure, beautiful appearance, excellent environmental resistance, long service life, light, thin, short, small and other characteristics, membrane switches conform to the development direction of high integration and high intelligence of modern electronic instruments, so they are favored by high-tech products

second, the particularity of film switch printing

silk printing has always paid attention to decorative effects since its invention. In addition to the common commercial features, another common feature is that in order to achieve the decorative effect, good reproducibility of colors and patterns and color rendering ability of inks are required in the printing process

1. Functional ink

color design, color reproducibility and ink color rendering are important factors to measure the quality of film switches, but the more important factors to measure the performance of film switches are the conduction function of film switches and the reliability of conductive circuits. Even if the film switch panel layer has the best color design, color reproducibility and oil, apply a thin layer of MoS2 (2 molybdenum sulfide) grease regularly; If the color rendering of ink loses the conductivity of the switch, the output of composite polyurethane adhesive used in the field of plastic flexible packaging in China in that year will reach 215000 tons, and the reliability of the function and conductive circuit will be in vain

the conduction function of thin film switch and the reliability of conductive circuit depend on the use of functional ink and other treatment measures. The functional inks used in thin film switches mainly guide silver paste, conductive carbon paste, high-performance conductive silver, carbon ink and insulating ink

the conduction function of the film switch and the reliability of the electric circuit there are not only related to the quality of the functional ink, but also closely related to the correctness and rationality of the circuit design in the manufacturing process, the plate making and printing methods, such as the control of the thickness of the plate photosensitive material (photosensitive glue or photosensitive film film), too thick photosensitive film layer will cause the waste of expensive functional ink and increase the manufacturing cost; However, too thin photosensitive film will seriously affect the conductivity of the membrane switch

2. Substrate treatment

the functional ink (silver paste) in the film switch is printed on polyester film (PET) through silk leak printing. Because of the relationship between the characteristics of silver paste and pet, pet must be treated before printing to ensure the smooth operation of printing and the firm adhesion of silver paste pet

(1) heat setting treatment

the silver paste circuit printed on pet can be cured only after being heated and dried in a tunnel oven or oven at 130 ° C for about 30min. Only after this process can the silver paste circuit have conductivity. In order to prevent the risk of film shrinkage of PET after being subjected to 130 ° C high temperature treatment, pet must be heat set before printing or pet that has been subjected to overheating setting treatment must be purchased directly

(2) surface polarity treatment

through corona bombardment and other treatments, a layer of polar groups of hydrophilic ink is obtained on the surface of pet, so that the silver paste has a firm adhesion on pet

(3) electrostatic protection treatment

due to the influence of static electricity, the pet surface is very easy to absorb dust in the air. The electrostatic elimination treatment on the pet surface before printing can greatly improve the printing quality and ensure the conductivity of the silver paste circuit

3. Strict quality inspection system

in the quality inspection of membrane switch, in addition to the color rendering of ink and the color reproducibility required by customers, it is more important to pay attention to the internal quality of membrane switch, such as key force, service life, peel strength, high temperature, low temperature, constant damp heat, return line resistance, insulation resistance, withstand voltage and other detection indicators

III. thinking about high-tech silk printing

silk printing is integrated into high-tech film switch manufacturing technology. In addition to the above contents, there are many new contents different from traditional silk printing, such as computer-aided design (CAD) of film switch circuit and manual wiring design; The design of the window and air duct of the isolation layer; Insulating ink and its ultraviolet (UV) curing application; Application of non-metallic conductor carbon paste; The working environment and storage environment of the membrane switch are controlled by the high-tech computer digital control (CNC) electronic auto focusing precision punch. Obviously, we should consider the working environment and storage environment of the membrane switch. Obviously, we should consider the structural design and material selection of membrane switches according to the working environment and storage environment of membrane switches. Nowadays, silk printing has developed into a new modern silk printing technology integrating high and new technologies such as optics, mechanics, electricity, chemistry, photochemistry, microelectronics, computers and so on. It is because of this point

IV. summary

membrane switch technology in its panel layer production has not only the color reproducibility and ink color rendering that are concerned in traditional silk printing, that is, the decorative function of traditional silk printing, but also the circuit conductivity in its circuit layer production. In recent years, it is necessary to continuously expand the electrical performance of aluminum utilization, prevent the oxidation of silver paste circuit and the migration of silver ions The high-tech content of the manufacturing of multilayer interchange circuits and the reliability of membrane switch products is obvious

source: International Packaging