In recent years, the development speed of UV ink technology at home and abroad is very fast, mainly reflected in the following points.
1. Cationic photo-curing system UV ink cationic UV curing system UV ink is currently a research area of ​​concern, because the system UV ink has the following advantages.
1) It is not inhibited by oxygen, which is conducive to high cross-linking of the ink surface, making the coating tough and shiny. The free radical light curing system ink is severely inhibited by oxygen.
2) The cationic UV curing ink does not generate unpleasant odors after curing, and once cations are generated upon irradiation with UV light, the curing reaction can continue after the light is stopped, which is beneficial to the deep curing of deep ink layers and the deep ink Curing, which is difficult for a free radical photocuring system to achieve.
3) After the cationic UV curing system UV ink is cured, the volume shrinkage is small (usually 3% to 5%), so it is beneficial to improve the adhesion to the substrate. Free radical photocurable inks usually shrink by 10% after curing, which greatly affects the adhesiveness of the substrate.
Therefore, the use of cationic light curing system UV ink or free radical/cationic composite light curing system UV ink can increase the speed of light curing, especially for the curing of colored UV inks and screen printing UV inks with thick ink film. For the benefit. The market growth rate of the cationic curing material is higher than the overall growth rate of the UV curing market. It can be seen that the UV ink using the cationic light curing system or the radical/cationic composite light curing system will be the new direction of UV ink development.
2. Water-based UV inks In addition to the characteristics of UV inks that are less polluting on the environment, water-based UV inks have lower viscosity, better rheology, and have a certain mitigation effect on oxygen inhibition. It solves some technical problems that early solventless UV inks cannot apply in gravure printing and flexo printing, and is suitable for gravure printing and flexographic printing.
3. The mixed ink is printed with ordinary ink. Only after the ink film is completely dried and UV glazing is performed, can a good glazing effect be obtained. Therefore, if on-line coating is used, the coating effect is not ideal. If you perform off-line glazing, in order to prevent back-smearing of the printed matter during the drying stage, it is necessary to spray the powder, and dusting will cause the sand surface of the original bright and smooth surface of the printed sheet to affect the appearance of the printed stencil.
Mixed ink is a new type of ink prepared by mixing ordinary ink components with UV curing materials. The ink is printed on a conventional sheet-fed press and irradiated with UV light, and then UV glazing can be performed on-line, and the UV varnish can be rapidly cured on the paper to obtain a uniform high gloss glazing effect.
Mixed ink printing has the following features:
1) Mixed ink printing combines the characteristics of UV-cured ink and traditional offset printing ink, so that the ink can be UV-cured to maximize the characteristics of UV ink. The ink can be instantly cured, greatly reducing energy consumption, reducing production, storage, and disposal costs and increasing production efficiency.
2) Mixed ink printing does not have to use special ink roller, blanket and fountain solution. In this way, mixed inks can be used when on-line glazing is required, and ordinary inks are used when not glazing. As is the case with normal ink printing, different ink rollers, blankets, and mixed inks may have some effects when used together.
3) Printing with mixed inks, the gloss will not fade after UV coating, especially suitable for printing products with high demand for ink coverage.
4) The ink balance of the mixed ink is relatively easy to control. Because the UV component in the mixed ink does not cure without being irradiated by the UV lamp, the mixed ink is always flowing on the printing machine and does not cause crusting on the ink roller like a normal ink and causes a printing failure.
5) Printing with Mixed Ink Due to instant drying, UV coating can be applied on-line on the press without the need for water-based varnishes. Its print quality is no worse than ordinary offset inks.
6) The mixed ink can print clear dots and improve the printing quality.
7) At present, most CTP plates should not be printed using UV inks, but they can be printed using a mixture of inks.
8) Less investment with mixed inks. For printers that already have UV technology, they only need to purchase a mixed ink. For printers that do not use UV technology, after investing in mixed inks, they only need to invest in UV curing equipment and UV lamps.
9) The mixed ink has a wide range of applications, and is suitable for printing on plastics, aluminum foils, metal papers and other very absorbent substrates in addition to printing on paper. Solved the problem of ink drying on non-absorbent substrates.
10) In addition to the use of sheetfed printers, mixed inks can also be used in narrow web presses.
Mixed inks are now being used more and more to print products with high gloss requirements, such as photo albums, pharmaceuticals, and cosmetic packaging boxes.
1. Cationic photo-curing system UV ink cationic UV curing system UV ink is currently a research area of ​​concern, because the system UV ink has the following advantages.
1) It is not inhibited by oxygen, which is conducive to high cross-linking of the ink surface, making the coating tough and shiny. The free radical light curing system ink is severely inhibited by oxygen.
2) The cationic UV curing ink does not generate unpleasant odors after curing, and once cations are generated upon irradiation with UV light, the curing reaction can continue after the light is stopped, which is beneficial to the deep curing of deep ink layers and the deep ink Curing, which is difficult for a free radical photocuring system to achieve.
3) After the cationic UV curing system UV ink is cured, the volume shrinkage is small (usually 3% to 5%), so it is beneficial to improve the adhesion to the substrate. Free radical photocurable inks usually shrink by 10% after curing, which greatly affects the adhesiveness of the substrate.
Therefore, the use of cationic light curing system UV ink or free radical/cationic composite light curing system UV ink can increase the speed of light curing, especially for the curing of colored UV inks and screen printing UV inks with thick ink film. For the benefit. The market growth rate of the cationic curing material is higher than the overall growth rate of the UV curing market. It can be seen that the UV ink using the cationic light curing system or the radical/cationic composite light curing system will be the new direction of UV ink development.
2. Water-based UV inks In addition to the characteristics of UV inks that are less polluting on the environment, water-based UV inks have lower viscosity, better rheology, and have a certain mitigation effect on oxygen inhibition. It solves some technical problems that early solventless UV inks cannot apply in gravure printing and flexo printing, and is suitable for gravure printing and flexographic printing.
3. The mixed ink is printed with ordinary ink. Only after the ink film is completely dried and UV glazing is performed, can a good glazing effect be obtained. Therefore, if on-line coating is used, the coating effect is not ideal. If you perform off-line glazing, in order to prevent back-smearing of the printed matter during the drying stage, it is necessary to spray the powder, and dusting will cause the sand surface of the original bright and smooth surface of the printed sheet to affect the appearance of the printed stencil.
Mixed ink is a new type of ink prepared by mixing ordinary ink components with UV curing materials. The ink is printed on a conventional sheet-fed press and irradiated with UV light, and then UV glazing can be performed on-line, and the UV varnish can be rapidly cured on the paper to obtain a uniform high gloss glazing effect.
Mixed ink printing has the following features:
1) Mixed ink printing combines the characteristics of UV-cured ink and traditional offset printing ink, so that the ink can be UV-cured to maximize the characteristics of UV ink. The ink can be instantly cured, greatly reducing energy consumption, reducing production, storage, and disposal costs and increasing production efficiency.
2) Mixed ink printing does not have to use special ink roller, blanket and fountain solution. In this way, mixed inks can be used when on-line glazing is required, and ordinary inks are used when not glazing. As is the case with normal ink printing, different ink rollers, blankets, and mixed inks may have some effects when used together.
3) Printing with mixed inks, the gloss will not fade after UV coating, especially suitable for printing products with high demand for ink coverage.
4) The ink balance of the mixed ink is relatively easy to control. Because the UV component in the mixed ink does not cure without being irradiated by the UV lamp, the mixed ink is always flowing on the printing machine and does not cause crusting on the ink roller like a normal ink and causes a printing failure.
5) Printing with Mixed Ink Due to instant drying, UV coating can be applied on-line on the press without the need for water-based varnishes. Its print quality is no worse than ordinary offset inks.
6) The mixed ink can print clear dots and improve the printing quality.
7) At present, most CTP plates should not be printed using UV inks, but they can be printed using a mixture of inks.
8) Less investment with mixed inks. For printers that already have UV technology, they only need to purchase a mixed ink. For printers that do not use UV technology, after investing in mixed inks, they only need to invest in UV curing equipment and UV lamps.
9) The mixed ink has a wide range of applications, and is suitable for printing on plastics, aluminum foils, metal papers and other very absorbent substrates in addition to printing on paper. Solved the problem of ink drying on non-absorbent substrates.
10) In addition to the use of sheetfed printers, mixed inks can also be used in narrow web presses.
Mixed inks are now being used more and more to print products with high gloss requirements, such as photo albums, pharmaceuticals, and cosmetic packaging boxes.
Huasheng Plastic Co., Ltd. , http://www.stcosmeticscase.com