Enhancing Isku’s furniture production with a new biobased, non-staining adhesive

Isku has switched to Kiilto’s biobased, pH-neutral Kiilto Pro WRX 3070 adhesive in its furniture production. The new adhesive also has very low formaldehyde content. The change of adhesive has improved the quality, productivity and safety of Isku’s production process.

Finnish furniture manufacturer Isku recently started using Kiilto’s biobased Kiilto Pro WRX 3070 adhesive, developed specifically for the furniture industry. D3 class PVAc adhesives are used in the wood manufacturing industry for products such as doors, parquet flooring, kitchen and bathroom worktops, and shelving. 

The new WRX 3070 adhesive is pH neutral, so it will not stain the wood veneer to be bonded. The adhesive also has a low formaldehyde content, which means safer production and greater responsibility in the use of the product throughout its life cycle. 

“Since we switched to the new Kiilto adhesive, not a single quality deviation has been reported in production due to discoloured veneer. The cost efficiency of the production process has increased a great deal with the new adhesive,” says Isku’s Purchasing and Steering Manager Antti Koljonen.


Juha Rinne checks the adhesive result with Antti Koljonen and Jukka Holttinen.

Adhesive discolouration creates waste

A major problem in the furniture industry is the discolouration of wood veneer caused by the acidic pH of adhesive and the resulting loss of wood. For example, in oak veneering, acidic adhesive can discolour the glued area, resulting in these products having to be withdrawn from production. Koljonen says that in the past, hardly a week went by in Isku’s production without products discoloured by adhesive being detected.

“As a natural material, wood is unpredictable when it comes to discolouration, with some pieces being more prone to it than others.  Adhesive break-through – visible penetration of the adhesive into the surface of the veneer – is usually only visible at the end of the process, as when a table is being lacquered. When this happens, the discoloured product has taken time and resources away from the production process,” explains Kiilto’s Solution Manager Juha Rinne.

Due to the thinness of the veneer, a discoloured product cannot be sanded, processed or repaired, so it just creates unnecessary waste in the production process. 

“Kiilto’s WRX 3070 adhesive was developed to solve this problem. We managed to reduce the degree to which the adhesive can permeate the veneer by modifying the structure of the adhesive. In product development, we have succeeded in optimising the absorption and penetration of the adhesive without compromising on its other properties,” says Kiilto’s RDI Manager Jukka Jokela.

Kiilto’s advanced PVAc adhesive also allows for thinner veneers to be used. This translates directly into material and cost savings.

Biobased adhesive: a sustainable choice

Isku started using the new adhesive at Kiilto’s initiative. The first steps towards switching were taken about a year and a half ago. 

“As this is a genuine innovation, a lot of time was spent fine-tuning the adhesive’s properties. In addition to other properties, we wanted to make the adhesive biobased so that it would also be a sustainable choice for customers,” Jokela says.

“A low-odour adhesive like WRX 3070, which bonds quickly without staining wood and is low in formaldehyde, is unique on the market,” Rinne says.

Kiilto Pro WRX 3070 contains up to 95% less formaldehyde than commonly used adhesive products. It means that WRX 3070 has lower formaldehyde content than apple, for example.

“Isku’s production team is very pleased with the adhesive’s mild odour and the increased safety it offers. The formaldehyde content was of course safe even with the previously used adhesive, but it is always better to have almost no formaldehyde in the product,” Koljonen points out.


Antti Koljonen (right) and Juha Rinne at the Isku showroom.

Improving energy and cost efficiency

Kiilto Pro WRX 3070 adhesive has an extremely short pressing time, and does not require high temperatures during the gluing process. The low temperature saves energy, while the reduction in pressing time and the uniformity in surface treatment make the whole gluing process considerably more efficient. It has been estimated that a shorter pressing time can increase production efficiency by up to an average of 20 per cent. 

“Where in the past we used to press 500 table tops in a day, with the new adhesive we can reach 600. This is a considerable efficiency gain in production,” Rinne says.

A new innovation to get it right first time

Isku and Kiilto’s partnership has gone excellently. Koljonen is very pleased with Kiilto for informing Isku’s production proactively about the latest innovations that can make production more efficient, safer or of higher quality.

“I feel privileged that Kiilto told us about this latest innovation at an early phase in its development, and asked us if we wanted to test it in production. The new adhesive has enabled a large reduction in wastage,” Koljonen says. 

“Production runs smoothly when you do it right the first time.”