| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to quantitatively detect the generation of a defect being called fogging, which is specific for a gravure printing and is generated when a doctor blade cannot be sufficiently scrape off a printing ink from a printing plate, without depending on the skill of an operator. SOLUTION: An optical sensor is installed in the printing unit of a gravure printing machine. Then, a light quantity detected from a printing original plate itself and a non-image line section which is being printed, is compared with a threshold value being set and designated in advance through an amplifier and an operation device. Thus, the generation of a fogging defect is detected. |
