Abstract: A liquid for removing printing and screen printing inks consists of an essentially anhydrous mixture of (a) .gamma.-butyrolactone and/or N-methyl-2-pyrrolidone in an amount of up to 25% (v/v) and/or (b) propylene carbonate in an amount of up to 90% (v/v), and (c) up to 90% (v/v) of a high-boiling aromatic compound or a mixture of such compounds having a relative evaporation rate with respect to N-butyl acetate of 0.01 or less. Such a liquid can remove all printing and screen printing inks, and it is considerably less unhealthy than the known cleaning liquids.

Abstract: Apparatus for washing-down serigraphical frames by means of a cleaning liquid comprises a sing-like unit having V or U-shaped ends, in which unit the serigraphical frames are placed, a scavenging hose with affixed brush, a filter section, a circulation pump, a sludge discharge system and a recirculation system for liquid. The filter section comprises a filter tray having V or U shaped cross-sections and a loosely fitted recovable filter mat of a chemically resistant material, preferably a polyester coating glass fibre material or polypropylene, with optimum surface. The collected sludge is discharged at intervals through the bottom of the tank unit, the unit cleaning liquid is recirculated continuously after filtration and added with fresh cleaning liquid. The apparatus is equipped with a double-acting suction system for vapours from the cleaning liquid and involves substantial advantages to the working environment.

Abstract: A liquid for removing printing and screen printing inks comprising an essentially anhydrous mixture containing:(a) q-butyrolactone and/or N-methyl-2-pyrrolidone in an amount of 1-25% (v/v);(b) one or more propylene glycol derivatives selected from substituted propyl acetates and/or propylene glycol ethers; and optionally(c) a diluent selected from aliphatic compounds having a flash point above 22.degree. C. and a content of aromatic compounds below 1%; and/or(d) a surfactant, the amount of components (b), (c) and (d) constituting 99-75% (v/v) of the liquid.