3: Printing

Question 1

Offset Lithography - Process (4)

Answer 1

1. The printing plate has the reversed image to be printed, on its surface
2. The printing plate is kept dampened. Ink is applied to the plate but it is repelled from the dampened surfaces (non-image areas)
3. As the printing cylinder rotates the ink is transferred to the rubber blanket cylinder.
4. The ink, now on the rubber blanket cylinder, is pressed onto the paper or card as it is pulled between the blanket cylinder and the impression cylinder (these pull the paper through the machine)

Question 2

Flexography - Process (4)

Answer 2

1. Ink Roller: this transfers the solvent based ink from an ink pan to the Anilox roller
2. Anilox Roller: this meters the ink to a uniform thickness onto the plate cylinder
3. Plate Cylinder: the substrate (surface recieving the printed image) moves between the plate cylinder and the impression cylinder
4. Impression Cylinder: this applies pressure to the plate cylinder which transfers the image onto the substrate

Question 3

Screen Printing - Process (4)

Answer 3

1. The substrate (surface recieving the printed image) is set on a base and a stencil is pressed over it
2. A polyester/nylon mesh screen is tightly stretched over the stencil
3. Ink is placed on the top of the mesh screen and squeegeed to force the ink past the stencil and screen
4. the squeegee/blade is used to ensure that all of the ink is forced through (any excess can be scraped off)

Question 4

Gravure - Process (4)

Answer 4

1. An image is acid-etched on the surface of a metal cylinder
2. The cylinder is etched with cells of different depths (hold ink transferred to the substrate)
3. The cells are filled with ink and the other parts are wiped clean of ink
4. The substrate is then pressed against the inked cylinder on a rotary press and the image is transferred