The deal for the £2m-turnover manufacturer completed on Monday (24 October). The value of the deal was not disclosed.
Sun Chemical and its parent company DIC Corporation have acquired the shareholdings of GEM, along with its sister companies also based at its Pontypool premises: Applied Enzyme Technology, Gwent Sensors, Gwent Biotechnology Systems and LRH.
GEM director Les Embury, along with his fellow director Robin Pittson will remain as directors and GEM will not be brought under Sun Chemical's branding.
Talks between the two companies began around a year ago.
Embury said: “Printed inks in electronics, sensors and bio-sensors are a rapidly growing market so this was something that Sun was interested in. As a small company, we are always looking for ways to grow our business so it seemed a good choice for both sides to come to an arrangement.
“We have the ability to sell worldwide through our own distribution systems, however the leverage in Sun's chain and ability through its own principles to access the market directly will enable us to grow at a more rapid rate than we ever could do [alone].
“We find certain markets difficult to access, such as South America. But because of trading deals that have been struck between North America and South America, being a US-based company Sun already has this access.”
Founded in 1988, 25-staff GEM mainly manufactures pastes and inks for printed electronics. It produces around 100,000kg to 200,000kg of paste a year in its 1,900sqm premises.
According to Embury, it currently provides glucose detection strips to a global manufacturer and is in the process of developing a printed sensor to detect gluten levels in potatoes. Its sister companies contribute to various elements used in the production of the technology.
“The addition of Gwent’s diverse advanced electronic materials and tailor-made technologies will further expand Sun Chemical and DIC’s solutions portfolio for printed electronics globally,” said Mehran Yazdani, president of Sun Chemical Advanced Materials.
Embury added: “It has an R&D facility in the US, whereas currently if we need serious testing done we have to go to a local university and pay for it. We do everything ourselves at the moment so now we can free up many of our staff to concentrate on what they are good at."
In early October, Sun Chemical completed the acquisition of the Flint Group's European publication gravure division, an acquisition that was first announced in August but had to be approved by German regulators.
Last month, Sun launched its latest environmentally-friendly ink for pad printing.
Between them, Sun and DIC emply more than 20,000 staff and have annual sales of around $7.5bn (£6.1bn).
