Flexo printing characteristics and application of UV LED light source in flexo printing. Flexographic printing is a kind of relief printing. It is a kind of wheel-type relief printing that uses flexible and elastic rubber or elastomeric plates to print. Flexographic printing was used in 1890. At that time, rubber was used as plate, and its development was slow. It was not until the emergence of photosensitive resin flexible printing in 1970 that the plate-making speed and precision were greatly improved. Flexographic printing entered a new period of development. Flexographic technology has wide adaptability and can be applied to different printing materials. In addition to traditional paper, some non-absorptive printing materials such as cellophane, plastic film, plastic products, metal foil, glass products, etc., as well as thick cardboard and corrugated paper can be printed. The printing cost is low, the printing quality is close to offset printing, and the printing speed is fast. At the same time, the cutting, forming, die cutting, punching, folding, stamping, film coating or polishing processes can be connected into a production line. The production rate is very high, and the degree of automation is also very high, so in recent years, it has developed very fast, especially in the past few years. Packaging printing is widely used. At present, flexible printing, corrugated carton printing, sticker label printing, folding carton printing are almost all flexographic printing, some newspapers and magazines are also flexographic printing.

 

 

 

Flexographic printing is a process in which ink is transferred to flexographic plate by screen roller, and excess ink is scraped off by ink knife. Flexographic plate is mounted on the printing roller. The ink is transferred to the plate by screen roller, and then directly transferred from the plate to the surface of the substrate.

 

 

 

Flexographic ink has a low viscosity, generally at 0.1-2 Pa.s. It is a kind of ink close to Newtonian fluid. Because it is mainly used for printing and packaging materials, ink color should be bright, transparency should be good, and color should also be good. Flexographic printing ink layer is relatively thin, generally around 4 microns, so flexographic ink pigment content is also higher, generally in 12% - 18%.

 

 

 

In the formulation design of flexographic ink, polyester acrylate and epoxy acrylate with low viscosity, fast curing rate and good dispersibility and wettability to pigments should be selected as oligomers.

 

 

 

The application of UVLED light source in flexo printing further promotes the production of flexo printing pipeline, which is a step up in flexo printing technology.