The Killeen Corrugated Products plant in Ballyfermot in Dublin is to close by the end of the year.
The business, which employs 55 people, is owned by paper and packaging Smurfit Kappa. A spokesman for Smurfit said there would be around 30 redundancies at the plant, while the remaining workers would be re-deployed. Killeen's business would also be moved to other Smurfit plants.
SIPTU, which represents workers at the plant, said workers had been told that the closure followed a downturn in business from major customers, including Magners and Bulmers cider.
SIPTU organiser Pat Ward said the announcement came as a shock to workers as they had agreed improved efficiencies following the loss of jobs earlier this year. The union says it will be looking for improved redundancy packages.
