History and technique offlat-frame printing(printing à la lyonnaise)

The technique

The Brochier Soieries printing workshop has more than 3,000 printing frames; they are used every day for printing silk fabrics. A list of the stages involved in printing à la Lyonnaise can only give a remote and somewhat abstract idea of the beauty of this technique. A visit to one of the workshops is the only way to properly grasp the artistry involved, where the skill and sensitivity of the printer are the key to success.

However, to give you a better idea, we hope, of this method of printing, here are the different stages of the process:

Engraving

The engraver breaks down the designer’s original pattern according to the number of colours it contains. One frame has to be made for each colour. These frames are superimposed in order to produce the pattern in its entirety.
The composition of the pattern is also worked out again according to how much it needs to be enlarged, both in height and in width. This task of visually re-arranging the design’s proportions also falls to the engraver.
In order to make the frame required for printing, the engraver transfers the original design by photoengraving it onto a piece of synthetic gauze stretched over a metal frame – this used to be done with a piece of silk stretched over a wooden frame.

The proof

The proof is the first test print. The engraver prints it onto paper. It is used to check that the frames are accurately aligned.

Before printing the colours onto silk, several preliminary operations have to be carried out to ensure a first-rate print:

• • Matching, i.e. working out the chemical formulae of the colours that are going to be used and ensuring that they are faithful to the original design.
  • Making the colours, which will vary in composition according to the fibre being used: a critical operation that takes place in a separate area of the workshop known as the colour kitchen.
  • Positioning the fabric on the long printing table requires the utmost care. Here the registration of the design, i.e. the alignment of the patterns, is adjusted to precisely match the sequence of patterns and the overlapping of the colours.

Printing

Printing the silk can then begin, first with the outlines of the design, then the successive colours and, finally, the background. The craftsman uses a squeegee to drag the accumulated colour from one edge of the frame to the other. The colour then passes through the gauze mesh, which is protected by a special varnish, to dye the silk.
The fabric is then left to dry above the printing table; this is called airing or lifting the piece. Once it is dry, the fabric is steamed, i.e. subjected to the action of a more or less dry steam which fixes the dyes on the fibre.
Finally, the fabric is washed, a particularly delicate operation for silk. This is followed by the inspection, an indispensable quality-control stage to check the conformity of the silk, which must have the same feel as it did before printing.