Broglia, a print and pre-press firm near Poole, has blamed wilting margins for its plan to make 40 redundancies, according to GPMU branch secretary Steve Attwill.
The firms production director Iain Stewart said: "Nothing has actually been put on the table thats definite so we are in the early days of talking about it." Losses were "possible".
It has around 150 staff and is thought to be closing its mail line, said the union.
Last April, the firm bought another B1 sheetfed printer, Drogher Press, to take combined turnover to 11.5m.
Broglia Press produces magazines, leaflets and brochures on kit including an eight-colour Heidelberg Speedmaster and a five-colour KBA Rapida. An Agfa Galileo forms part of its pre-press line-up.
The news follows Huhtamaki van Leers move to cut 10% of the 480 staff at two packaging sites in Gosport.
"The UK market for our products has undergone major change in the vending, ice cream and dairy sectors," said human resources manager Colin Williams. Several staff had accepted voluntary redundancy in the 30-day consultation, he added.
Story by Jez Abbott
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