Dry phenolic process in spotlight

Last time WBPI spoke to Longoni Roberto e figli srl it was the summer of 2020 and, of course, the Covid-19 pandemic was in full flow.

Two years on, the pandemic has thankfully subsided and restrictions eased. For Longoni it has been a very busy time, characterised by R&D and healthy financials.

Longoni is a world leader in know-how, machinery and materials for the global panel surfacing and finishing sectors. It has a particular focus on developing countries and projects ranging from delivering a complete factory for HPL manufacture, to supply of presses, impregnation lines, resin plants, cutting and drying technology, cushion pads and press plates, as well as the ability to supply second-hand and reconditioned equipment.

Ludovico Longoni, executive director, explained that its customers in the board, HPL and short cycle laminate sectors have performed well, only registering a slight drop in turnover during the 2020 initial Covid crisis year.

“From our point of view, at the end of 2020 there was a stronger development of the market and we closed 2021 about 60% up compared to 2019,” he said.

“We expect this year to be 20% higher than 2021.”

“Now there is the strong issue of energy costs. Everyone is talking about it but the manufacturers are still full of orders. They are also increasing the prices – we see this in the newsletters we receive from customers.”

These issues of product price increases and rising energy costs, Mr Longoni added, are causing some anxiety in the market. And he cited some reports of board shortages for Italian furniture manufacturers.

“It’s a troubling period for everybody but still the market is very strong so this offsets all the shortcomings.”

“We have a very strong supply of impregnation lines for HPL and also in the lamination industry for particleboard. We also still have a strong market for decorative products like aluminium foils, decorative papers and also chemical additives.”

Mr Longoni reported strong demand and good supply for its melamine powder product, while current installation projects include a big impregnation line in Brazil and retrofitting at a large HPL manufacturer in Italy. The latter is eager to restart production because of strong demand.

The company is also working with factories in South America, the Middle East and India. “These markets had some ups and downs but the total turnover was not that affected.”

PHENOLIC RESIN DRY APPLICATION PROCESS

One of Longoni’s biggest focus developments in recent years has been working on substituting wet impregnation with a dry treatment.

As previously reported in WBPI, the LamiDry process is described as a new perspective in melamine resins application. Longoni has a pilot plant in Italy, where an MF resin, different from standard melamine resins, is optimised for lamination after powder coating.

Before the pandemic, Longoni and its partners were focused on this melamine powder application and it is in discussions with customers about establishing full scale industrial lines.

“In the last two years we have worked very hard on the phenolic application which proved to be really amazing as a result,” said Mr Longoni.

“The concept is that we are using phenolic resin in powder form – so no water or liquid.

The resin is melted and coated on the kraft paper. So the application line is no longer an impregnation line, it is melted solid resin, coated and the paper is ready to be used in the same cycles as the HPL industry.”

This dry phenolic process is also covered by the same patent and is called Phenolic Lami-Dry – kraft paper coated with dry phenolic resin which can replace the standard phenolic impregnated paper.

Advantages cited over traditional phenolic application include lack of fumes, zero emissions, removal of RTO air treatment, a much smaller footprint for the application equipment and operated by electricity (not gas).

Longoni has gone to the expense of adapting an existing industrial line in Italy to prove the process.

“We have a 25m-long industrial line which can run 300 linear metres per minute. If you compare a standard impregnation line which can run at 150m/min this will be at least a 100m length line.

“This changes the perspective of this industry a lot. After some lab developments we passed into industrial production and we made some full-scale production, producing around 15,000m2 of kraft paper with this coating with different parameters.

“We asked three major HPL manufacturers to test these papers in their standard processes. The results are very promising.

“Our general target is to supply to customers the package of know-how and industrial plant for production – our ideal customers are major HPL manufacturers who do not want to deal with liquid phenol anymore and want to go to a dry process.”

The equipment for the dry phenolic process is complex and developed in partnership with a European leader of coating machines.

“The investment is not small but the aim was to demonstrate to customers that this technology is ready to use and the result was very successful and all the customers could produce marketable HPL in their standard plants with small adjustments with our kraft papers,” said Mr Longoni.

“Now we are working to supply regular production runs to HPL companies. We are going through this step to make the customers convinced that the technology is working. This is really a completely different approach. When we showed this technology to production managers of the companies they could not believe it could work in this way.”

The process involves coating the surface of the paper, not soaking the resin into the paper. The technology allows the resin to melt in the press, basically impregnating the kraft paper in the same pressing cycle.

“The feedback was extremely exciting and we really believe it is a revolution for our industry.”

Mr Longoni said the three HPL manufacturers it has worked with are seriously thinking about introducing the dry phenolic process in their plants.

Longoni aims to regularly supply coated kraft paper from its plant to the customers, as the construction and delivery of an application line in Europe would currently take at least 16 months. “So we are ready to cover their demand for paper using this line we have already set up.”

And, of course, further development of the product is taking place all the time on the industrial test line.

“We are focusing on the launch of this technology at the next Ligna exhibition.

“The phenolic industry is very different from the melamine paper industry because it requires high capacity, very big attention on the cost side and quality is important. This gives the right properties for laminating with the lowest possible cost.”

Production takes place up to three to four times faster than an impregnation line and there is no need to have a resin manufacturing system on site as phenolic powder resin is widely available from many countries and has a shelf life of at least six months compared to around two weeks for liquid resin.

“We are also studying other advantages,” added Mr Longoni. “We think we have the possibility to use kraft papers with more recycled content, which would also help to reduce the costs and make the product more eco-friendly.”

In summary, Mr Longoni said the company has been studying and developing this technology for many years and believes it could be a strong option for customers.

“We believe that some customers can take a swift decision to invest in this technology.”

Full scale production of many tonnes of papers are planned in September for customers, while a first customer plant installation for Phenolic Lami-Dry is forecast within 18 months to two years.

With these technology developments, Longoni is moving forward with a melamine dry application process for digital print, specialist applications and very deep surface structures, while the phenolic dry application process has proved possible for standard kraft paper in high speed HPL production.