Shares of plastic products specialist Coral Products plunged after it warned full year results are expected to be substantially below the market's revised expectations as poor trading conditions persisted.The Merseyside based firm, which makes plastic cases for CDs and DVDs, said media sales, especially DVD sales, have been very disappointing in the last two months and are a major factor in the poor second half. It added that local authority cuts have had some effect on the group's recycling division and the extended cold weather has hurt the launch of its new ice cream food packaging products.While Coral confirmed that results for the year to April 30th 2013 would be substantially below the market's revised expectations, the board expects to return an overall profit for the year with EBITDA having shown significant growth."Whilst the group will continue to develop markets outside of the media sector, the sale of HMV and Blockbuster has stabilised the DVD market and the group is seeing signs of increased activity," it explained.Shares of Coral fell 21.1% or 2.38p to 8.88p at 09:00.CJ