PURPOSE: To enable light printing which is economical and finely precise by using the printed original obtd. by thermal transfer of the printing output from an information output terminal on original paper via a thermal head and ink ribbon directly as the block copy of an offset printing machine.

CONSTITUTION: The original paper 1 formed by printing on the original paper 1 subjected to a surface treatment so as to maintain hydrophilic and water retaining properties via the thermal head 3 for information signal output attached to the information output terminal and the ink ribbon 2 having high lipophilic and water repellent properties is used as the block copy. The fine particles of the lipophilic ink dispersed in water are, therefore, adsorbed selectively on the lipophilic printing part and the non-printing part is covered with the water and is prevented from being stuck with the particles of the hydrophilic ink. The ink patterns 4 of the block copy applied selectively with the ink in the printing part in such a manner are once transferred to a transfer cylinder 6 and are finally transferred to paper 7 by the principle of an ordinary offset printing machine. The simple and highly precise printing is thereby enabled.