Ink giant Sun Chemical will increase the cost of its sheetfed inks by 5% as of 1 March.

The company blamed "critical shortages" of raw materials such as acrylic acid and gum rosin, which have also suffered from "unprecedented" cost increases, for the move.

The cost of certain key raw materials has increased by more than 200% from the start of 2009 with further increases expected, according to Sun Chemical.

Vegetable oils are a major cost driver for all sheetfed inks and the supply and cost of linseed, rapeseed and soybean oil are "very complex and volatile".

Felipe Mellado, chief marketing officer at Sun Chemical, said: "The same raw materials that are having a tremendous impact on publication inks also affect sheetfed inks.   

"Vegetable oils are also a major contributor to the price of sheetfed inks. The supply of vegetable oils such as soya, linseed and rape are very volatile."

He added that prices had increased more than 40% from July 2010 and were expected to remain high for the first half of 2011.

"The entire printing industry is under tremendous strain due to raw material shortages and a very volatile supply situation, and therefore Sun Chemical will have to continuously monitor and review its prices to ensure efficiency," he said.

Factors such as the value of the dollar and crude oil prices suggest that vegetable oil prices will remain high compared to 2010.

Elsewhere, paper manufacturer Arjowiggins Graphic has announced an 8% price increase for its coated and uncoated graphic papers.

The increases will take effect from the middle of March 2011 and are a result of "dramatic and continuing rises" in the cost of energy and raw materials such as wood, waste paper and starch.

David Cook, managing director of Arjowiggins Graphic, said: "The rise in price has been driven by the increasing price of energy and raw materials such as wood, waste paper and, in particular, starch.

"These driving factors are completely out of our hands and so it would be difficult to estimate whether or not we can expect additional cost increases this year." 

This is despite implementation of cost reduction measures at its European mills. The increase will affect graphic paper reels and sheets.