Announcing the signing of the sale contract, Trimo said in a press release on Thursday that in the new ownership structure the company was to keep its development, decision-making and corporate brand independence.

"We are happy that Trimo will continue to develop independently and promote its brand on the global market, while also having the opportunity to share numerous advantages and benefits within the large Kingspan family," said executive director Božo Černila.

In-house trade unionist Peter Štrekelj said that the sale to the Irish building materials company had been expected as the outgoing owners had been announcing it ever since they acquired Trimo in December 2015.

"Perhaps it was a surprise in the light of the current events ... but I am happy that the new owner respects our independence and that no major changes are expected when it comes to employees," he added.

Elena Fink, the head of the works council in Trimo, is also satisfied with the sale. She said that the great interest in the company proved its high standing on the list of successful companies in this industry.

Since the previous takeover, Trimo has strongly increased its market share in panels with mineral wool core to around 10% and has become the second largest maker of the product in the world.

The share of revenue generated abroad has also been on a rise since 2016, when it stood at 22%, while last year it reached 35%, and the company said that as part of Kingspan it could even better utilise its potential.

Under the outgoing owner, the company focused on the existing clients and reduced activities to win major, one-off projects, while also streamlining operations and abandoning certain programmes. This was aimed at improving profitability.

"The successful transformation of Trimo during the Innova Capital ownership is an excellent example how an equity capital owner can help develop a Slovenian company at international level. It was an intensive and very creative period," said Černila.

Trimo sells its products made in plants in Slovenia and Serbia mostly in Western, Central and East Europe. Its brand is present in more than 60 countries around the world, and it has its own sales network in almost 30 countries.

Established in 1965, Kingspan has developed from a small family business into a group employing around 15,000 people and having 159 production plants. It is present in 70 and is global market leader in the high-performance insulation segment.

The company, which has grown primarily by means of takeovers, had unofficially been interested in Trimo years ago.