HP Brilliant-Ink chemists prove the impossible is anything but!
Saba Lotfizadeh, Paul Bruinsma, Christina Rodriguez, Gregg Lane, John Stoffel
A few decades ago, HP scientists and engineers were challenged to dramatically improve photo image quality. We knew that for our customers, preserving their precious moments was of utmost priority. So, we got to work, doing all that we could to ensure images printed on HP printers would stand the test of time. To accomplish this, our inkjet images would need to meet or exceed silver halide image permanence performance. We needed help, so we brought in a consultant to breakdown the magnitude of our mission. We spent the following days learning how light fade permanence is measured and how current silver halide prints perform. At the end of his visit, the consultant boldly stated that “we were wasting our time and HP would never achieve the needed permanence.” Determined to prove the expert wrong, ink chemist John Stoffel wrote down this quote and showed it to our group of chemists and engineers.
Looking back, it’s easy to see how someone from the silver halide industry could have such a poor opinion of the potential of inkjet. In the early 80’s, the beginning days of inkjet, HP employed less than 10 chemists. Purified food dyes were used as the colorants, hardly the necessary ingredients to deliver photo quality prints. However, by the mid 90’s, we had grown our chemistry capability and were going after photo-quality prints. We had the best colloidal, physical, inorganic, and analytical chemists working in our labs. HP also had the best ingredients in its inks and began to enter development relationships with world-class chemical companies across the globe. This meant working with leading chemical companies in the United States, Switzerland, Germany, Great Britain, and Japan. In fact, when we found the company that made the best magenta dyes, we entered a development project with them to make an even more saturated and permanent magenta dye. We also learned who made the best pigment dispersions and entered a joint development to create a more stable pigment dispersion capable of firing through a nozzle smaller than a single human hair. We also partnered with paper companies to understand the composition and variation of common papers and worked with photographic paper companies to create a superb paper for inkjet photos. With our growth in both knowledge and support, it came as no surprise that we were able to match silver halide performance with dye-based chemistry within five years. Shortly afterward, we developed pigmented ink that surpassed it.
The next decade presented us with a new challenge—developing ink for HP’s PageWide Web Presses. This was a new business for HP, utilizing our proven technology based on thermal inkjet but applied on the massive scale of a continuous feed web press. The ink would need to meet both quality and exceptional printhead life goals as well as print on any uncoated paper. We were able to leverage many aspects from HP’s work in consumer and office printing, such as our pigmented ink technology. We were also quick to understand the paper that needed to be printed as it was a close cousin to the copy paper that HP had printed on in the office.
While HP’s legacy of groundbreaking print innovation had always prepared ink chemists to tackle the road ahead, enabling the printhead life, presented a new challenge. Home and office printers only need to print millions of drops per nozzle, or at most a few liters of ink per printhead in its lifetime. In contrast, PageWide printers would use billions of drops of ink per nozzle or barrels of ink in just a matter of days or weeks. Using this amount of ink meant we needed to increase each printhead's lifetime by orders of magnitude. Although the challenge was great, HP chemists had already proven they could produce. To help them deliver, HP assembled a special team of scientists and engineers. Together, they developed the next generation of dispersions, an improved combination of surfactants and solvents, and a polymer binder to enhance performance. With these additions, our printhead life goals reached our target of billions of drops per nozzle to satisfy our customer needs. Challenge met!
Most recently, our team of innovators was again put to the test. Their mission—to ensure PageWide presses are able to print directly onto offset coated papers, vital for the direct mail market. Our customers had grown accustomed to using coated media for offset printing with traditional analog presses for their print jobs. Over the decades, it was perfected for oil-based inks. We considered the issues this paper would present with our water-based inks, and it wasn’t pretty. The calcium carbonate or clay particles that are glued together with latex binders result in low surface energy and absorptivity, which caused typical inkjet inks to bead up, coalesce, and produce ugly print quality. Think of what happens when you use a marker to write on a piece of tape. You write something and the ink pools up on the surface, which causes smearing and creates a big blob. This is basically what happens with water-based inkjet inks on offset coated papers.
Saba Lotfizadeh was one of the first chemists on the Brilliant Ink project. As a new hire, she was eager to learn about the high value of direct to offset printing with water-based inks. And when she discovered the challenges associated with it, Saba moved quickly to find a solution. With some of her early ink designs, Saba produced customer representative printouts that showed high-quality images boasting stunning uniformity, high gloss, and breath-taking color. It was at that moment our team realized that they’d unlocked HP’s answer to revolutionizing the direct mail market! Saba’s promising ink designs united an entire team of chemists and engineers dedicated to perfecting her solution. The determined team designed the ink to spread evenly into large thin layers with improved color, ink efficiency, and gloss. They even used state-of-the-art printhead designs for optimal drop ejection. These designs enabled an innovative approach to paper wetting and penetration behavior by using new surfactant and solvent packages — resulting in excellent image quality. In fact, these prints were so beautiful, it seemed only right to call the finished product, “HP Brilliant Ink.”
HP Brilliant Ink was a bold move, however, implementing it on to a web press still remained a challenge. Our customers needed a full-service solution and through earnest collaboration, that’s exactly what our team provided in the PageWide Web Press T250 HD with HP Brilliant Ink. Numerous breakthroughs, including HP Optimizer, enabled the incorporation of our new ink invention into our web press system, as did a focused effort from our team of chemists and top-notch engineers. This new capability to produce high-quality prints in vivid colors on offset coated and uncoated media didn’t just astonish our customers, it inspired a generation of chemists and engineers for years to come.