Woodblock Printing - Technique

Technique

The wood block is carefully prepared as a relief matrix, which means the areas to show 'white' are cut away with a knife, chisel, or sandpaper leaving the characters or image to show in 'black' at the original surface level. The block was cut along the grain of the wood. It is only necessary to ink the block and bring it into firm and even contact with the paper or cloth to achieve an acceptable print. The content would of course print "in reverse" or mirror-image, a further complication when text was involved. The art of carving the woodcut is technically known as xylography, though the term is rarely used in English.

For colour printing, multiple blocks are used, each for one colour, although overprinting two colours may produce further colours on the print. Multiple colours can be printed by keying the paper to a frame around the woodblocks.

There are three methods of printing to consider:

Stamping

Used for many fabrics, and most early European woodcuts (1400–40). These items were printed by putting paper or fabric on a table or a flat surface with the block on top, and pressing, or hammering, the back of the block.

Rubbing

Apparently the most common for Far Eastern printing. Used for European woodcuts and block-books later in the 15th century, and very widely for cloth. The block is placed face side up on a table, with the paper or fabric on top. The back of the paper or fabric is rubbed with a "hard pad, a flat piece of wood, a burnisher, or a leather frotton".

Printing in a press

"Presses" only seem to have been used in Asia in relatively recent times. Simple weighted presses may have been used in Europe, but firm evidence is lacking. Later, printing-presses were used (from about 1480). A deceased Abbess of Mechelen in Flanders in 1465 had "unum instrumentum ad imprintendum scripturas et ymagines ... cum 14 aliis lapideis printis" ("an instrument for printing texts and pictures ... with 14 stones for printing") which is probably too early to be a Gutenberg-type printing press in that location.

In addition, jia xie is a method for dyeing textiles (usually silk) using wood blocks invented in the 5th-6th centuries in China. An upper and a lower block is made, with carved out compartments opening to the back, fitted with plugs. The cloth, usually folded a number of times, is inserted and clamped between the two blocks. By unplugging the different compartments and filling them with dyes of different colours, a multi-coloured pattern can be printed over quite a large area of folded cloth. The method is not strictly printing however, as the pattern is not caused by pressure against the block.