A key component of aqueous pigment inkjet ink formulation is the pigment dispersion. Fujifilm’s RxD pigment dispersions are a proven technology in high-performance print systems worldwide: in Fujifilm inks for their own systems and used by other ink manufacturers.
In this interview with Product Manager, Grant Murney, and Technical Manager, Wendy Boyd, Fujifilm offers insights into why RxD dispersions are ideal for high performance waterbased inks.
Aqueous pigment inkjet technology is expanding in many applications. How do RxD pigment dispersions meet the demands of aqueous ink formulation?
Grant: Ink formulators must meet more and more demanding specifications for functionality, productivity, and compliance. As the foundational component in ink, they need high-quality dispersions to enable them to meet those specifications. Fujifilm’s RxD pigment dispersions are highly stable. That’s the key advantage of RxD. They are designed for creating high-performance inks across a diverse range of water-based inkjet applications in packaging, textiles, industrial and commercial printing.
What makes RxD suitable for this range of applications?
Wendy: The exceptional stability of RxD dispersions means they can be used with a wide range of ink formulation components, like strong cosolvents and aggressive surfactants. This flexibility is critical for designing inks to challenging specifications. The high pigment concentration gives further flexibility in achieving the right formulation.
Ink formulators will always be looking for a dispersion that helps them to efficiently meet the specification. Thanks to its versatility, RxD can streamline and enhance the efficiency of the ink development process. Also, RxD colors are cross-compatible between our ranges, so the dispersion selection can be tailored to a particular application. We believe that RxD is one of the highest-performing inkjet dispersions available today. They are suitable for indirect food contact packaging applications, and GOTS approval and OEKO-TEX® certification for textile inks.
Stability is a recurring theme. What is the technology that achieves that stability?
Wendy: RxD dispersions use a proprietary precision stabilization process that “locks” each pigment particle in a cage of cross-linked polymer. It’s an elegant design, creating a high-quality, robust dispersion. The stability also gives it a long shelf life. We have an experienced R&D team of polymer specialists, physical scientists, pigment dispersions specialists and analytical experts working on this. They are very driven when it comes to finding innovative solutions.
To what extent are RxD dispersions used in aqueous inkjet systems today?
Grant: RxD dispersions are well proven within Fujifilm’s high-speed, high-quality single-pass printers, and through our global customer base using RxD in inks in their print systems across all key print sectors. This encompasses proven reliability across an extensive variety of printheads from key manufacturers and includes small printhead architectures, such as MEMS.
What are the challenges when working with smaller printhead architectures?
Wendy: Quality is critical. RxD's tight particle size control is essential for small printhead architectures with higher resolutions, and smaller drop sizes. RxD is manufactured to a high purity, which is critical for reliable jetting performance, and we use high-quality inkjet-grade pigments. We took our experience, technology, and advanced manufacturing capabilities in clean solution thermal inkjet inks to develop our processes for producing high-purity pigment dispersions. This is why we can achieve such precisely controlled particle size, minimal levels of polyvalent ions and trace organics, and specification consistency.
How do RxD dispersions contribute to the advancement of demanding future applications, such as flexible packaging?
Grant: For packaging, RxD is being used in the design of inks for fiber-based and filmic substrates. In flexible packaging, achieving good adhesion with low-viscosity aqueous inks requires the use of more aggressive components in the formulation to create a strong interaction with the substrate or primer, and achieve fast drying. Typically, these components would destabilize the pigment dispersion. A highly stable dispersion provides the flexibility to employ a broader range of components to build the right functionality and characteristics for the ink in demanding applications.
As print speeds are pushed higher, faster drying inks are needed. This means inks have the potential to dry faster on the printhead and affect print quality. The formulation versatility of RxD makes them very suitable to choose the right solvents and humectants to achieve the ideal balance of those properties.
Also, as the drive for pigment inkjet in the textile sector increases, evidenced by the number of pigment machines at the 2023 ITMA exhibition, RxD dispersions have an important role in helping ink formulators to achieve the wash fastness, crock, color, and softness required in home textile and fashion applications.
How can ink formulators access Fujifilm’s dispersion technology?
Grant: RxD dispersions are available through the FUJIFILM Ink Solutions Group, you can contact our team through www.fujifilmink.com. These products are manufactured at our two dispersion manufacturing sites – one in the UK, and the other is our recently commissioned facility in the USA, following Fujifilm’s $47 million investment in aqueous dispersion manufacturing.
