| 摘要 |
PURPOSE: To prevent the putrefaction of a developer in an automatic developing machine and to prevent the contamination of a planographic printing plate to be processed by adding a specified compd. to the developer and/or a replenishing developer. CONSTITUTION: The developer for a photosensitive planographic printing plate contains an alkali agent and at least one kind of compd. selected from specified compds. These specified compds. to be added are pyridinethiol-1-oxide, salicylic acid, 1,3,5-tris hydroxyethyl hexahydro-S-triazine, 1,3,5-tris hydroxymethyl hexahydro-S-triazine and alkali metal salts of these. Alkali metal salts such as sodium salt, potassium salt, and lithium salt are preferable, and especially, salt of pyridinethiol-1-oxide and 1,3,5-tris hydroxymethyl hexahydro-S-triazine are preferable. |
