The Japanese-owned company, Arklow Pottery, is to close in April with the loss of 140 jobs due to oversupply in international markets and competition from lower cost producers in Asia.
The owners said the decision was taken with regret, but they saw no prospect of restoring commercial viability after losses of more than £7 million over 20 years.
The plant, the biggest of its kind in the Republic, has been in Arklow since 1934, and some of its workers have been with the company for more than 30 years.
The company has been a subsidiary of the Japanese company, Noritake, since 1977. Noritake also owns tableware plants in Japan, Sri Lanka and the Philippines.
The financial director, Mr Eamon Fox, said Noritake had rescued the plant when it ran into trading difficulties under its previous owners, Arklow Pottery, a public company.
But he said it had losses of about £7.5 million under the ownership of Noritake, and since 1994 and a £750,000 investment programme, there had been continued losses.
"We did achieve break-even for a number of years. We have lost £500,000 over the past two years on an annual turnover of about £3 million," he said.
Arklow still has Qualceram producing sanitary ware, and a pottery-producing company, Wicklow Vale, but Mr Fox said that plant was involved in giftware, which did not rely on the same volumes of output as the tableware "industrial pottery".
"Based on our experience, we think that another industry would have the same basic structural problem and costs problem as Noritake has had," he said.
He said there had been layoffs over the past 15 years after the number of workers peaked at 480 in the early 1980s. Workers had been put on short time last year, amounting to a loss of six weeks each, which had been added on in holidays.
He said that redundancy terms would amount to three weeks per year for the first 10 years, after which it "goes down slightly".
A separate Noritake porcelain factory in Arklow closed in 1985 with the loss of 135 jobs. Some 1,000 workers were at one stage employed between the two plants.
Last November Noritake sold the vacant 150,000 sq ft building, where the fine bone china had been produced, to Qualceram for £850,000.
The plant is closing despite a "continuous programme of product and process improvement and investment".
Mr Fox said that three years ago there was investment in new forming equipment for the ceramic product. "We hoped that this would help us to reduce our cost base but competition got even more cut-throat.
"We are in a worldwide market for tableware. It is a mature market and does not grow much," he said.
He said that over 70 per cent of the produce was exported to US markets, with only 15 per cent sold in Ireland.
The SIPTU official in Arklow, Mr Paudge Reddy, said the closure announcement came as a complete surprise. "There had been difficulties over the past two decades with fluctuations in demand and increased competition, but it would be fair to say that people at the plant are stunned," he said.
He added that a meeting of workers will take place on Tuesday and the prospects of finding replacement jobs will be discussed. Production at the plant is due to wind down at the end of April.
"In the meantime I will be contacting the IDA and the Government to investigate what measures can be taken to limit the impact of this devastating blow," he said.
The Fine Gael TD for Wicklow, Mr Billy Timmins, said Arklow had been the unfortunate victim of a number of job losses in recent years and the closure of the pottery firm was a "devastating blow".
"It is now imperative that the Government, and especially the Tanaiste, Ms Harney, pulls out all the stops to locate a replacement industry of similar size in Arklow as soon as possible," he said.
An Independent councillor, Mr Nicky Kelly, called on Ms Harney to establish a task force for the area and to address the "serious and escalating unemployment in Arklow and south Co Wicklow".
Mr Vincent McElheron, a county councillor, said successive government ministers had neglected the loss of jobs in the area. "Skilled handcraft expertise will once again be lost to posterity unless there is a local takeover of Arklow Pottery," he said.