| 摘要 |
<p>New lithographic layer (I) for printing blankets comprising a polyurethane (II) based thermoplastic material (III) incorporating a copolymer of ethylene vinyl acetate (IV) to confer a polar quality guaranteeing an optimum transfer of ink from (I) to the paper. Also claimed is a printing blanket or sleeve comprising (I). Preferably (II) is an ethylene-propylene copolymer. (III) incorporates bulk, such as magnesium silicates, aluminium silicates, or metal oxides, and plasticisers (for example an ester or a polymer). For 100 parts of (II), (I) contains 0-20 parts by weight of (IV), 0-30 parts by weight of bulk and 0-10 parts by weight of plasticiser. (I) contains at least one pigment (0-2 parts by weight for 100 parts of (III)). (II) has a polar component in water, formamide and dimethyl sulphoxide of 0-20 mJ/m<2> (5-12 mJ/m<2> in water and 0-10 mJ/m<2> in formamide preferred). (I) is used in printing. Because (I) has a significant polar component, virtually all the ink is transferred from (I) to the paper. This ensures a good quality print and avoids the need to clean or change the printing blanket too frequently.</p> |
