Gumming solution for use in the burning-in of offset-printing plates comprising water, a hydrophilic polymer and an organic acid derivative

A solution for use in the burning-in of irradiated and developed offset-printing plates, consisting essentially of an admixture of (a) enough water to solubilize water-soluble components in said solution, (b) at least one water-soluble hydrophilic polymer selected from the group consisting of poly-N-vinyl-pyrrolidone-(2), polyvinyl methylether, a copolymer containing ethylene units and maleic anhydride units, a homopolymer or copolymer containing at least one from the group consisting of vinyl phosphonic acid units and vinyl methyl phosphinic acid units, and a polyalkylene glycol and (c) at least one component derived from an organic acid, wherein (i) said component (c) comprises at least one water-soluble organic acid comprising at east two acid functions and being selected from the group consisting of a benzene carboxylic acid, a benzene sulfonic acid, a benzene phosphonic acid, and an alkane phosphonic acid, or a water-soluble salt thereof;

• (ii) about 1 to 50% by weight of said solution is comprised of components (b) and (c), which are present in a weight ratio ranging from about 1:1 to 1:20, and (iii) said solution is capable of producing, even after burning-in a totally water-soluble layer.