Does inkjet ink contain salt in its composition? The ink secrets that you don't know and are often overlooked!

At present, thousands of different types of inks are used in various industries, especially in continuous inkjet printing, to directly code and mark products and packaging through ink. However, how much do you know about ink itself? Leibinger, a global leader in coding and marking system innovation, is a company that produces both coding printers and ink. It has been digging into the secret world of industrial ink and discovering some interesting facts that you may not know. This article, following Leibinger's perspective, takes us into the wonderful world of industrial ink.
TOP 01
Anti counterfeiting UV ink has the same composition as laundry detergent
Invisible UV ink can be used as an advanced anti-counterfeiting solution, which verifies the authenticity of products by adding hidden markings or codes that are not visible to the naked eye. However, conventional UV colorants pose a risk of easy availability: this ingredient is widely present in household laundry detergents (its blue purple hue can neutralize yellowing of clothing and maintain visual whiteness). As an anti-counterfeiting measure, invisible UV ink is only effective when it is difficult to replicate.
To this end, the new anti-counterfeiting ink adopts composite color development technology, which enhances the difficulty of imitation through multi band spectral response. For example, black ink exhibits green fluorescence under ultraviolet light, and this cross color response requires precise molecular structure design, making it difficult for ordinary counterfeiters to reproduce. This technology constructs an insurmountable anti-counterfeiting barrier by increasing the spectral feature dimension.
TOP 02
The harder the PVC, the easier it is to print
The global annual production of PVC exceeds 40 million tons. Its pure texture is brittle and hard, requiring the addition of plasticizers to enhance flexibility. For example, the plasticizer content in hard plastic pipes is much lower than that in flexible cable sheaths and food packaging films. Although ink can perfectly adhere to PVC molecules, it is difficult to adhere to plasticizer molecules. Therefore, printing on hard pipes is easy, but printing on materials with high plasticizer content such as food packaging and cables is quite challenging. This can lead to the phenomenon of "ink migration" - when ink cannot adhere, it can easily contaminate the surface of adjacent items.
In response to this challenge, new ink formulations have emerged on the market, which have completely overcome the technical bottleneck of printing adhesion by enhancing the binding force with plasticizer molecules.
TOP 03
Using invisible UV ink to make product packaging more beautiful

UV ink is not only safe to use, but can also be used to enhance the aesthetic appeal of products. If brand owners believe that visible barcodes or batch numbers will damage the appearance of their high-end packaging, they can choose invisible UV ink printing. Many products that are visible on a daily basis actually carry coding information that is not visible to the naked eye. These invisible markings can only be presented when exposed to ultraviolet light, which not only enhances the beauty of the product, but also plays a role in anti-counterfeiting and traceability.
TOP 04
Green and environmentally friendly ink is more difficult to produce, but it is worth promoting
Mixing colors is as easy as pie, but there are hidden mysteries in how to develop environmentally friendly ink. To evaluate the environmental friendliness of ink, it is necessary to analyze its core components: industrial packaging ink needs to have ultra fast drying properties, with about 80% of its formula being solvent components. After the solvent evaporates, the remaining substances are mainly adhesives and coloring agents. In traditional formulas, solvents and adhesives are mainly based on petroleum, which poses significant environmental challenges for ink manufacturers. Leibinger has now broken through the technological bottleneck and launched an innovative formula - with bio based ingredients accounting for up to 85%, significantly reducing the pressure on global resource consumption.
TOP 05
A perfect ink formula requires a small amount of salt
In addition to solvents, colorants, and adhesives, there is another secret ingredient in continuous inkjet ink that not everyone knows - salt. This is because continuous inkjet technology requires an electrostatic field to charge each droplet of ink, so that it can be guided by a deflection electrode to the surface of the substrate to form text and patterns. The addition of salt substances is precisely to enhance the conductivity of the ink and ensure that the ink can respond to electrostatic deflection commands. As all excellent chefs know well - a good chef is a handful of salt.
TOP 06
Every letter received contains UV ink
Machine readers, such as the millions of scanners used in postal sorting systems, work more efficiently when paired with UV ink. This ink has stronger recognizability compared to ordinary black and white printing. When the letter arrives at the sorting center, an optical character recognition (OCR) scanner reads the recipient address and then prints the barcode with UV ink. The subsequent scanner can quickly and accurately recognize the barcode, thereby accelerating the circulation of letters in the postal system. If you have ever been curious why there are often faint orange or pink barcodes printed on emails, now the answer has been revealed
TOP 07
Ink characteristics reflect specific customer needs
Sometimes you may want printed numbers or barcodes to be permanently visible, but some customers also require ink that can be removed under specific conditions. Therefore, we must develop inks with different persistence or washability.
Taking the shelf life label of recyclable glass bottles as an example, when empty bottles are recycled and refilled, the old shelf life needs to be removed by a corrosive solution prepared by the bottle factory, and the new date needs to cover the original position. However, due to the frequent contact of these glass bottles with moisture (whether it is condensation from ice buckets or condensation droplets generated when taken out of the refrigerator in high temperature weather), the ink must have sufficient water resistance to ensure that it cannot be erased by ordinary water alone.

Although PET bottles cannot be refilled, ink stains still need to be removed during recycling to avoid residual pigments contaminating the whiteness of recycled materials. However, the temporary requirements for certain markings are more extreme - in automobile manufacturing, rolled aluminum plates are usually printed with batch numbers, but when the aluminum plates are stamped into body parts, these codes must be easily removed. Customers often have a gradient difference in their demand for ink durability, which depends on their product characteristics and the end user's usage scenario. Therefore, customizing ink formulas with different adhesion according to needs is the core value of all ink manufacturers.
TOP 08
Many printer manufacturers are unable to produce their own ink
Leibinger has a long-standing reputation as an industrial inkjet printer and industrial printing ink manufacturer. This means that we can assist our customers in achieving more precise, efficient, and sustainable printing results, as we have a deep understanding of the underlying logic behind the synergy between ink and printers. This is fundamentally different from many printing equipment companies that rely on third-party ink supply - the latter can only indirectly verify the ink chemical formula through the "composition analysis report" provided by the ink manufacturer. Although ideal results can be achieved in most cases, it cannot replace the practical verification of different inks tested on different printers.