Cloth-Printing Machine Pressers covered with India-rubber.

Practical Magazine 20, 1876

(Chemistry applied to the Arts, Manufactures, &c.
Dyeing, Calico Printing, Bleaching, Tanning, and Allied Subjects.)

In the Bulletin de la Société Industrielle de Rouen an account is given of the pressers covered with india-rubber invented by M. BOURDON. Ever since 1836 fruitless attempts have been made to substitute for the endless cloth of printing machines a covering adhering to the presser. M. Bourdon's pressers are covered with two layers of india-rubber, the one black, hard, adhering to the metal, and half an inch thick; the other olive yellow, not so hard as the former, and rather more than a quarter of an inch thick. This second layer is turned at the graver, and polished with strong emery paper before being set in motion. The turning of the rollers requires certain precautions, according to circumstances.

The bulging for rollers of 6½ ft. to 7¼ ft. diameter ought to be not more than about a twentieth of an inch. With more bulging the printing would be fainter at the edges than in the middle of the texture. Apart from the pressure to be given, which is less, the working is exactly the same as by the ordinary process.

The colours, whatever their mode of thickening, are worked with the usual consistence. The pressure being diminished, they do not penetrate the texture so much, and consequently give a better return. The experiments by the authors of the report were made on machines with one or two colours, but they do not doubt that they would have been equally successful on machines with several colours.

When by chance a hard substance, such as a nail, passing between the doubler and the presser is indented in the covering of the latter, all that is necessary is to pour into the indentation a mixture of gutta-percha and india-rubber, melted with a hot iron, removing the excess with a very fine file.

The reporters, comparing the expenses occasioned by the use of endless cloth with those of the vulcanized presser, reckon the latter not much more than one-fourth of the former; there is also a considerable saving in labour.

It has been found that whenever a machine with two colours is stopped, and the presser removed, the pattern is not displaced, as is the case with the endless cloth.

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