A lithographic printing plate surface protective agent is provided, which exhibits an excellent capacity to prevent fingerprint scumming on a post-platemaking lithographic printing plate. This lithographic printing plate surface protective agent comprises at least one compound represented by the following general formula (I)
R-O-(CH2CH2O)n-H (I)
(in the formula, R is a C14 to C22 alkyl group and n is the average number of moles of addition of an ethylene oxide group and is 20 to 60).
本发明提供了一种平版印刷板表面保护剂,它能很好地防止印后平版印刷板上的指纹浮渣。这种平版印刷板表面保护剂至少包含一种由以下通式 (I) 表示的化合物
R-O-(CH2CH2O)n-H (I)
(式中,R 为 C14 至 C22 烷基,n 为
环氧乙烷基的平均添加摩尔数,为 20 至 60)。