Light-curing plastic coatings
In today’s materials and processes continue to collide with the fusion, giving rise to unlimited innovation, light-curing ink coatings like a shining star of science and technology, glittering in many areas, especially for the gorgeous transformation of plastic products have made great contributions. From the shuttle in the city streets of the car parts, to the precision operation of all kinds of equipment; from carrying a huge amount of information on the CD-ROM, to decorate the living space of the decorative panels; and even with our daily consumption of closely related credit cards, as well as those widely used in the field of cutting-edge technology, metallization equipment, light-curing coatings have found a place to use, giving the original ordinary plastics to the extraordinary characteristics.
It is like a magical wizard, gently waving a magic wand, can make the plastic glowing with charming gloss, so that it shines brightly in the light, instantly enhancing the texture of the product. Moreover, the plastic after it, light stability greatly enhanced, whether it is a long time exposed to sunlight, or in a special environment of strong light, can keep the color bright, appearance as the first, effectively resisting light aging brought about by fading, deformation and other issues. Abrasion resistance is even better, daily friction, scratching can not help it, greatly extending the service life of plastic products. At the same time, in the chemical protection level, light-curing coatings for plastic wearing a layer of sturdy “protective clothing”, so that it can resist the erosion of various chemical substances, to ensure that the plastic in the complex use of the scene safe and sound.
However, just as flaws inevitably appear in the carving process of beautiful jade, light-curing ink coatings will also encounter some difficulties when processing. As a result of a variety of complex factors intertwined, will inevitably produce some defects, these defects are like points of “black spots”, so that the plastic originally due to the gloss greatly reduced, and aesthetics are also affected. Not only that, the conventional plastic’s own scratch-resistant, solvent-resistant and anti-aging properties, just like a weak “line of defense”, it is often difficult to resist the outside world, unable to meet the many high-end or special application scenarios of the stringent requirements. Therefore, fine medical decoration and comprehensive protection of plastic surfaces has become a key issue in the field of plastics processing nowadays.
In-depth exploration of the world of plastic substrates, that can be said to be a wide variety, each with its own characteristics. The common ones are polystyrene (PS), polymethyl methacrylate (PMMA), polyvinyl chloride (PVC), polyethylene (PE), polypropylene (PP), polyester (PET), polycarbonate (PC), ABS engineering plastics and so on. Their surface properties are as varied as the human character, PET, PMMA, PS and other substrate surfaces have a certain polarity, as if they come with “affinity”, making light-curing coatings and they can be more smooth “hand in hand”, adhesion problems are relatively Adhesion problems are relatively easy to overcome. However, PE and PP substrates are very different, their surface polarity is extremely low, like a cold “island”, and light-curing coatings between the existence of a large “disconnect”, poor adhesion. In the face of this dilemma, researchers and engineers can be said to have racked their brains to come up with a series of ingenious ways. For example, in advance of the PE and PP substrates for corona, corrosion and other polarization treatment, as if to the “island” built a bridge, so that the coating can be successfully boarded the island; or in the coating formula carefully add adhesion promoter, act as a “bride” between the two to promote their close integration. In short, the “magic” of light-curing coatings on the surface of low-polarity plastics really needs to overcome a lot of difficulties and put in a lot of effort.
Look at the light-curing coatings in different shapes of plastics on the coating method, that is also quite delicate. For flat plastic parts, including common pipe, roller coating method is like a skillful painter in the hands of the brush, can be uniform, smooth coating on the surface of the plastic, to ensure that every place can be perfectly covered. The three-dimensional shaped plastic parts are like an exquisite sculpture, spraying method is more adaptable to its complex shape, like a fine spring rain, the paint evenly sprinkled in all corners, to achieve a full range of decoration and protection.
It is worth mentioning that the light-curing plastic coating itself has some unique “little temperament”. Its viscosity is usually low, around a few hundred millipascals・seconds (mPa・s), like a clear spring with excellent fluidity. In order to further optimize the performance of the coating, formulators often add a small amount of silicone-based leveling additives, which act as lubricants, giving the coating extraordinary leveling properties, making the surface of the light-cured plastic as flat and smooth as a mirror, ensuring that high-quality decorative effects can be reaped.
PVC flooring material, for example, this kind of plastic parts in the coating curing, wear-resistant, anti-scratch performance has very high requirements, after all, it has to withstand frequent daily tread, friction. At this point, the choice of coating formula is critical. Should be selected after curing the texture of hard oligomer and active diluent, they are like building a plastic protective fortress “cornerstone”, solid and reliable. At the same time, reasonable adjustment of the ratio of hard components and flexible components, as mixing a perfect symphony, so that the various parts of the synergistic power. Then add the appropriate inorganic fillers and nanomaterials, these “trace elements” can further strengthen the wear resistance of the plastic, so that its abrasion resistance to get a qualitative leap, in the process of prolonged use can still maintain a clean as new.
Looking ahead, with the continuous progress of materials science, we might as well boldly assume: If researchers can develop a new light-curing coating system, it is not only able to perfectly adapt to all types of plastic substrates, regardless of the polarity of the high and low, but also according to the specific needs of different plastics products, intelligent adjustment of their own hardness, flexibility, gloss and other properties, it will bring what kind of revolutionary changes in the plastics processing industry? What kind of revolutionary changes will it bring to the plastics processing industry? This will undoubtedly greatly simplify the production process, reduce production costs, so that the quality and performance of plastic products to a whole new level. It is believed that in the near future, with the deepening of the research, this beautiful vision is expected to become a reality.
In addition, in order to facilitate the industry in the actual production of reference, Table 1 to Table 17 lists the details of different plastic substrate light-curing coatings reference formula, these formulas cohesion of countless scientific researchers wisdom and practical experience, is to open the door to the application of light-curing plastic coatings of the invaluable key.
| Photoinitiator BP | 3.00% |
| N-Methyldiethanolamine | 2.00% |
| Photoinitiator 1173 | 1.00% |
| EO-TMPTA Monomer | 85.50% |
| HDDA Monomer | 9.50% |
| Photoinitiator 184 | 2.00% |
| DPPA Monomer | 30.00% |
| TMPTA Monomer | 30.00% |
| EDGDA Monomer | 20.00% |
| furfuryl alcohol | 5.00% |
| KH-570 | 100% |
| Silica gel powder | 70.00% |
| Leveling agent | 0.03% |
| Photoinitiator 1173 | 1.00% |
| Photoinitiator BP | 5.00% |
| Tertiary Ammonium Modified Acrylate | 4.00% |
| Aliphatic Urethane Acrylates | 70.00% |
| NVP | 10.00% |
| Aliphatic Monofunctional Acrylates | 10% |
| Leveling agent | 1.00% |