PURPOSE: To obtain marking processing liquid which is stable for a long time and shorten time for etching treatment by including 1 kind or more of phytic acid and/or metallic salt of the phytic acid and/or ammonia chloride and primary to tertiary amine compound to be expressed by a specific formula.
CONSTITUTION: Desensitization processing liquid not including cyanogen compound at all to be used for processing an electrophotographic offset printing plate face is manufactured by including at least 1 or more kind of each of phytic acid and/or metallic salt of the phytic acid and/or ammonia chloride and primary to tertiary amine compound to be expressed by a general formula written in the right side. In the formula, the total number of carbon atoms of R1-R3 is 9 or more, R1 expresses 6C or more aliphatic group, R2 and R3 express hydrogen and aliphatic group, forming a ring structure according to circumstances. Also as the amine compound, 1 class amine compound to be expressed by a general formula R4-NH2 (R4 expresses 6C or more aliphatic group) is used, adding to or replacing the above-mentioned compound.
KASAI KIYOSUKE
SERA HIDEFUMI
KATO EIICHI
