Advanced paper whitening with higher sustainability and cost control

Archroma’s new concept brings a reduced OBA dosage, which means fewer chemicals in the process and a reduced environmental footprint.

By Dr Andrew Jackson

There is every reason to believe that optical brightening agents (OBAs) will have a bright future, despite the highly competitive market in which we find ourselves today. After all, whilst there is a steady decline in production volumes of office papers, there has been a continued interest worldwide in producing papers to higher levels of whiteness and contrast.

Archroma, a global leader in colour and speciality chemicals, has developed a new concept that gives papermakers the ability to produce truer, cleaner whites with improved print contrast and appearance while reducing consumption of optical brightening agents (OBAs) by up to 20 percent.

With OBA production capacity, well-exceeding demand, purchasers focused on unit price have been able to take advantage of some remarkably low offers in the marketplace. It is therefore not surprising that suppliers resort to desperate measures to save on costs and remain in business.

At the same time, some legitimate reductions in OBA pricing have been made possible through lower raw material costs in certain areas. Since 2009, the dollar price of diaminostilbene disulphonic acid (DAS)– the raw material with the greatest cost contribution to di- and tetrasulphonated OBAs – has fallen by more than 20 percent.

The production cost of hexasulphonated OBAs, on the other hand, has been adversely impacted by a price increase of 65 percent for the key ingredient, aniline-2,5- disulphonic acid. Nonetheless, reports in the marketplace are that OBA imports into certain countries are continuously priced below domestic market prices, resulting in market share gains for importers.

We also recognise a trend towards increasing use of high-yield pulps (HYP), with their obvious sustainability advantages over low yield, bleached chemical pulps. Yet the key to the successful implementation of HYP is the ability to reach the higher brightness levels of chemical pulps. While peroxide bleaching has been the traditional route to higher brightness levels of HYP, recent studies have promoted OBAs as a more sustainable solution.

Focus on cost and sustainability

In today’s challenging marketplace, there is a strong focus on cost and sustainability. The latter is of critical importance to the paper industry. Yet there are both economic and environmental components to sustainability- suppliers need to remaincompetitive while investing in making improvements to quality that reduce environmental impact. 

If OBAs might not seem to be the most obvious source of sustainability gains, a closer look shows that significant reductions in the environmental footprint can be made by their correct application.

The ongoing use of optical brighteners as an environmentally responsible and cost-effective means of producing high-contrast white papers will depend on technological developments from those few established producers having the ability to offer innovation and service across a complete whiteness package.

Dedicated Research & Development

Complementing a Research and Development team dedicated specifically to paper, Archroma’s Paper Solutions Business provides expertise in the management of whiteness, coloration, special coatings and strength for all kind of papers. By offering a combined focused product range and the application services of paper experts around the globe, Archroma is able to enhance both the optical and functional properties of paper.

The company’s experts constantly optimise production processes for customers and improve and innovate products and services after carefully listening to market needs. Depending on customer requirements regarding performance, cost and application, they offer tailor-made solutions to help meet the industry’s key challenges. Archroma’s research and development team based in Reinach, Switzerland, is continuously testing new concepts and developing new products, with the specific aim of offering customers further innovations, such as in the area of concentrated OBAs.

In April 2016, Archroma launched its‘Advanced Whitening’ concept, integrating the use of concentrates and bringing their application benefits to a higher level. This two-component package combines the use of Leucophor® products with a newly launched surface shading dye called Cartawhite® XL liq.

Archroma had already raised the bar a few years earlier when it developed its innovative Leucophor XL whitening system. This range allowed papermakers to break through their whiteness ceiling to reach previously unattainable levels. The Leucophor XL range improved whiteness build-up without destroying brightness for coated and uncoated papers and board.

Based on five years of research and development, the new, patent-pending Advanced Whitening concept allows users to optimise both OBA and shading components when producing their printing, writing and office papers. By allowing the separate dosing of these two components (OBA and shading dye), Advanced Whitening provides paper makers with the means to reduce their whiteness costs across all grades while producing a paper with an extraordinarily true, clean white appearance that affords excellent print contrast.

In addition, the concept shows good compatibility with size-press and coating systems and reduces two-sidedness compared with 100 percent pigment shading systems. In addition to cost-saving across all grades of printing and writing papers, the new concept brings a reduced OBA dosage which means fewer chemicals in the process and a reduced environmental footprint. Advanced Whitening offers papermakers around the world levels of flexibility they have never seen before.

Author: Dr Jackson is a Global Product Manager, Optical Brightening Agents, Paper Solutions Business, Archroma.

© Chemical Today Magazine

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