The deal, which was signed on Monday afternoon (27 July), creates a £100m print group, but Unite is fearful of similar job cuts and changes to terms and conditions that were made at Wyndeham following its acquisition by Walstead in December.
"Of all the groups in all the world, Wyndeham is the last one that we would have wanted to take on a company like Southernprint," said Unite national officer Steve Sibbald.
"It has slashed and burned through the whole [Wyndeham] group since it was taken over by Walstead, with wage cuts and increases in hours, all the worst possible conditions, backed by the threat of unemployment."
"Our [Wyndeham] members, are not going to be happy that a company that cried poverty has bought another firm. That's going to go down like a lead balloon," added Sibbald.
"However our primary concern now is as the company is looking to consolidate, will they close down Southernprint or perhaps one of the other Wyndeham sites? I can't see why they would keep all the sites going if there's too much capacity in the market."
However, Wyndeham chief executive Paul Utting, who along with group finance director Andy Page has joined the Southernprint board, stated at the time of the deal: "Southernprint will play an integral part in the future of the enlarged Walstead Group. Having two large, similarly equipped web offset printing sites will enable the combined Group to provide greater flexibility and contingency for customers.
"We will sit down with Southernprint’s management teams in the next few weeks to review the operations and managements of the two groups, with a view to identifying commercial advantages and efficiencies which can be used to give our customers a better service and product offering.
Despite the union's concern over the deal, it was generally welcomed by the magazine print buying community as step towards much needed consolidation in a sector stricken with overcapacity, although some did raise fears over the prospect of too much consolidation in the web offset sector.
"This deal has got to be good news, because there is a lot of overcapacity in the [magazine] market, with too many people chasing not enough work," said William Reed production director Christopher Reed.
"Is it good that the industry is going down the consolidation route? That's a tough call, because consolidation just means that there will be fewer players in the market for the print buyer, and that's a concern."
Unite hits out over Walstead's Southernprint acquisition
Print union Unite has reacted with anger over Wyndeham Press Group owner Walstead Investment's purchase of Southernprint.