Intaglio, Gravure or Photogravure Printing

Gravure is a method of printing from a cylinder or plate in which the design is sunken below the surface as distinguished (в отличие) from relief printing. Intaglio printing is produced from copper cylinders and plates on sheet –fed and web rotary machines.

The gravure processes which provide the printing surface on the cylinder or plate are almost completely photographic in technique.The sunken portions are cells which hold the ink for impression. We know the cells to be of constant width, which is determined by the screen (растр) used. Screen may be as fine as 300- line, but normal work requires a 150- line screen or approximately 22,000 cells to the square inch. The deeper the etch (травление) the darker the tonal value.

As gravure cylinder is ground and polished to close tolerance (малый допуск) no make- ready (приправка) is necessary. Therefore the first impression is as clear and sharp as the last one and the gravure process does not depend upon individual skill and experience as any other printing method. To make a printed impression, the cylinder or plate revolves in the ink container so that the cells will be filled with ink. Then the cylinder revolves further and the surplus (излишек) ink is mechanically wiped off by a steel scraper (скребок) leaving the non-printing surface clean but permitting the ink to remain in the cells. The cylinder now completes its revolution and the ink remaining in the cells is transferred to the moving web by pressure exerted by a rubber impression roller. This roller presses the web against the engraved cylinder and the web lifts the ink from the cells.

Задание 2. Выберите утверждение, соответствующее содержанию текста.

1. The printing surface on the cylinder or plate is provided by:

a. a printing methods

b. almost photographic methods

c. a scraper

2. The darker tonal value is made by:

a. shallow etch

b. inking

c. deeper etch

3. The ink remaining in the cells is transferred:

a. to the moving web

b. to the cylinder

c. to the ink container

4 Intaglio printing is produced from a cylinder or plate:

a. in which the design is raised above the surface

b. in which the design is on the plane

c. n which the design is sunken below the surface

Text 3C

Задание 1. Прочтите текст, отыскивая в нём ответы на поставленные вопросы.

1. What is sheet- fed gravure?

2. What presses is sheet – fed gravure done on?

3. What presses is rotogravure done on?

4. What image carriers are used for sheet – fed gravure?

5. What image carriers are applied for rotogravure?

Date: 2016-05-14; view: 416; Нарушение авторских прав