The curing performance of ink is the most critical factor in determining the quality of UV printing products. Therefore, when choosing UV ink, the main consideration is whether the emission wavelength of the UV lamp used in our printing equipment matches the triggering wavelength of the photoinitiator in the ink. In addition, the key properties such as curing speed and adhesion of different types of UV ink provided by different manufacturers are also not the same. Generally speaking, as long as white ink and black ink can meet the requirements, other color schemes of ink will not have too many problems. Therefore, black ink and white ink should be carefully examined.
The wavelength range of UV light is 200-600nm, but ozone is generated at a wavelength of 254nm, while heat is generated above a wavelength of 400nm. Ozone pollution pollutes the environment and damages the health of workers; Heat not only causes dimensional instability and even severe deformation of printed materials, but also leads to energy waste, both of which we do not want to occur in UV printing.
At present, low-energy UV (UV/LED) lamps sold in the market emit wavelengths between 280-600nm. Although they avoid the ozone band, they still contain a significant amount of heat generation. Therefore, LED lamps have become a new development direction for UV light sources in recent years. The available wavelengths for single wavelength LED lights are 365nm, 385nm, and 395nm, avoiding the ozone and heat generation bands. Moreover, the light energy of single wavelength light sources is highly concentrated, resulting in high ink curing efficiency and safer use.
Select UV ink based on its compatibility with UV light sources
The prerequisite for UV ink curing is the irradiation of UV light, and the photoinitiator in the ink can absorb its energy and generate free radicals. Under the action of free radicals, the resin and single-molecule compounds in the ink can undergo cross-linking reactions, causing the ink to solidify.
The triggering wavelength of traditional UV ink photoinitiators is generally 220-580nm, while the triggering wavelength of low-energy UV ink photoinitiators is 280-400nm. LED-UV ink photoinitiators mainly absorb UV light with a wavelength of 365-400nm. When choosing UV ink, the first thing to consider is whether the wavelength range sensitive to the ink corresponds to the emission wavelength range of the UV lamp used by the company. At the same time, the actual curing energy of the UV curing system should also be taken into account to determine the specific model of UV ink.
Comparison between the trigger wavelength of UV ink photoinitiator and the emission wavelength of UV lamp
Reference Knowledge 344/1000 Reference Knowledge 344/1000 Translation Machine · General Field: Choosing UV ink color based on the curing performance of black ink and white ink also affects the curing speed of UV ink. Different colors of ink have different curing speeds (see Figure 2), mainly because each pigment has different absorption rates for ultraviolet light of different wavelengths. Among all color schemes, magenta ink is the easiest to cure, while black ink is the hardest to cure. The influence of ink color on curing speed is because although black theoretically absorbs all light and should have high curing efficiency, pigment particles have a blocking effect on light, which hinders the curing of deep ink. Therefore, black UV ink requires high curing energy, and the curing speed of black and various dark inks is relatively slow. The high energy required to cure white ink is due to the fact that white pigments can achieve total reflection of all visible light, which makes it difficult and slow to fully cure white UV ink. The curing efficiency of ink series is directly related to white ink and black ink. As long as there is no problem with white ink and black ink, other colors of ink can be used with confidence. Translation Machine · General Field Select UV ink based on the curing performance of black ink and white inkColor also has an impact on the curing speed of UV ink. Different colors of ink have different curing speeds (see Figure 2), mainly because each pigment has different absorption rates for UV light of different wavelengths. Among all color schemes, magenta ink is the easiest to cure, while black ink is the most difficult to cure.The influence of ink color on curing speedThis is because although black theoretically absorbs all light and should have a high curing efficiency, the pigment particles have a blocking effect on light, which hinders the curing of deep ink. Therefore, black UV ink requires high curing energy, and the curing speed of black and various deep color inks is relatively slow.The high energy required for curing white ink is due to the fact that white pigments can achieve total reflection of all visible light, making it difficult and slow to completely cure white UV ink.The curing efficiency of an ink series is directly related to white ink and black ink. As long as there is no problem with white ink and black ink, other color inks can be used with confidence.
Select UV ink based on the curing performance of black ink and white ink
Color also has an impact on the curing speed of UV ink. Different colors of ink have different curing speeds (see Figure 2), mainly because each pigment has different absorption rates for UV light of different wavelengths. Among all color schemes, magenta ink is the easiest to cure, while black ink is the most difficult to cure.
The influence of ink color on curing speed
This is because although black theoretically absorbs all light and should have a high curing efficiency, the pigment particles have a blocking effect on light, which hinders the curing of deep ink. Therefore, black UV ink requires high curing energy, and the curing speed of black and various deep color inks is relatively slow.
The high energy required for curing white ink is due to the fact that white pigments can achieve total reflection of all visible light, making it difficult and slow to completely cure white UV ink.
The curing efficiency of an ink series is directly related to white ink and black ink. As long as there is no problem with white ink and black ink, other color inks can be used with confidence.
