Tag Archives: pulp and paper

Ink toner on paper: research into topographies

An April 14, 2015 news item on Nanowerk about pen (in this case, ink toner) and paper,

A team of Finnish scientists has found a new way to examine the ancient art of putting ink to paper in unprecedented 3-D detail. The technique could improve scientists’ understanding of how ink sticks to paper and ultimately lead to higher quality, less expensive and more environmentally-friendly printed products.

Using modern X-ray and laser-based technologies, the researchers created a nano-scale map of the varying thickness of toner ink on paper. They discovered that wood fibers protruding from the paper received relatively thin coatings of ink. In general, they also found the toner thickness was dictated mainly by the local changes in roughness, rather than the chemical variations caused by the paper’s uneven glossy finish.

“We believe that this gives new insight, especially on how the topography of paper impacts the ink setting or consolidation,” said Markko Myllys, an applied physicist at the University of Jyvaskyla in Finland. “This in turn helps us understand how glossy and non-glossy printed surfaces should be made.”

An April 14, 2016 American Institute of Physics (AIP) news release (also on EurekAlert) by Catherine Myers, which originated the news item, describes the research in more detail,

To achieve their detailed picture of ink thickness, the researchers first examined the underlying paper with X-ray microtomography, a smaller cousin of the CT scanning technology used in hospitals to produce images of the inside of the body.

To analyze the cyan ink layers, the researchers used two additional technologies: optical profilometry, which bounced a light beam off the surface of the ink to obtain a surface profile, and laser ablation, which zapped away controlled amounts of ink with a laser to determine the ink depth.

Although none of the imaging techniques are themselves new, the researchers were the first to combine all three to achieve a complete, high-resolution 3-D image of the intricate ink and paper microstructures.

The final images resemble a rugged mountain landscape, with the higher peaks generally showing thinner coatings of ink, and the valleys showing thicker pools.

The researchers found the typical ink layer was approximately 2.5 micrometers deep, about 1/40 the thickness of an average sheet of paper, but with relatively large spatial variations between the thickest and thinnest areas.

Knowing how topographical variations affect ink thickness will help the printing industry create more environmentally-friendly and less energy-demanding ink and optimize the size distribution of ink particles, Myllys said. It could also help the papermaking industry design more sustainable paper and packaging, for example from recycled components, while still maintaining the quality needed to make ink stick well. Additionally, the papermaking industry could use the findings to help decide how best to incorporate smart and novel features into paper, Myllys said.

The team believes the imaging methods they used can also be adapted to effectively analyze the thickness variations in other types of thin films, including those found in microelectronics, wear-resistant coatings and solar panels.

“This result can certainly be generalized, and that makes it actually quite interesting,” Myllys said. “Thickness variations of thin films are crucial in many applications, but the 3-D analysis has been very difficult or impossible until now.”

Here’s a link to and a citation for the paper,

X-ray microtomography and laser ablation in the analysis of ink distribution in coated paper by  M. Myllys, H. Häkkänen, Korppi-Tommola, K. Backfolk, P. Sirviö, and J. Timonen1. J. Appl. Phys. 117, 144902 (2015); http://dx.doi.org/10.1063/1.4916588

This paper appears to be open access.

Nano and India’s pulp and paper industry

PaperTech 2014 is the latest version of a pulp and paper industry conference held annually (?) in Hyderabad, India. A May 26, 2014 news item on Azonano describes an upcoming session at the conference being held June 20 – 21, 2014,

Industrial Nanotech, Inc., an emerging global leader in nanotechnology based energy saving solutions, is pleased to announce that they have received and accepted an invitation from the steering committee to present at PaperTech 2014, the annual conference that focuses on improvements and new technologies for use in India’s pulp and paper industry.

An Industrial Nanotech May 23, 2014 news release on Stockhouse.com,  which originated the news item, describes the current situation for India’s pulp and paper industry,

There is an increased focus in India by pulp and paper and other manufacturers on energy savings as liquid natural gas prices increase. According to Bloomberg News, India’s cabinet agreed to a price increase to double the $4.2 per million Btu price to $8.4 per million Btu starting April 2014. Conservation of energy is vital to the pulp and paper industry in India, which is expected to grow at the CAGR (Compounded Annual Growth Rate) of around 9.6% during 2012-2017, which will make their revenues reach up to USD 11.83 Billion by 2017.

The company, Industrial Nanotech, provides information on its website about energy-saving products in various industry sectors including pulp and paper on their Nansulate®
webpage, Scroll down about 1/4 of the way to find a summary of the Seshasayee Paper & Boards Ltd. case study/presentation at PaperTech 2011 (PDF of the full case study here).

I was not able to find a dedicated PaperTech 2014 conference site but I did find this conference registration/info page on 10times.com.