Production at the Flaxall factory in Carrickfergus was not affected by a fire which destroyed two printing machines in April 1980.
Part of the roof was also destroyed.
Workers were forced to flee the premises when, it is understood, a pipe fractured and a leakage of inflamamble liquid triggered off a minor explosion and started a fire.
An engineer was slightly injured and was taken to the Royal Victoria Hospital where he was treated for slight burns to his shoulder and a swollen ankle.
The management said that damage to the building was slight. Workers returned to the factory after being given the all clear from the fire brigade.