22.5.22

New Method of Calico-Printing.

The Manufacturer and Builder 9, 1875

Under the name of Argentine is known a style of calico-printing in which metallic luster is imported to the woven tissue. Two or three modes of doing this have been practiced, none giving very satisfactory results. Finely-divided silver-leaf or precipitated tin is mixed with an alkaline solution of casein and printed on the fabric from a block or roller. The metallic luster in brought out by heavy colendering and hot-pressing.

Silver is particularly sensitive to the action of sulphurouns fumes; and, as such fumes are always present more or less in the atmospheres of towns, fabrics thus prepared soon become blackened and unsightly. Tin in therefore, preferable for this purpose, and should be prepared by precipitation from a diluted solution by means of zinc. A few pieces of sheet zinc are placed upright in a vessel capable of containing about a couple of gallons. Into this is poured about 6 quarts of a weak solution of zinc chlorid in which has been dissolved 100 grains of stannons chlorid or tin salt. Finely-divided metallic tin in precipitated, and when the action has ceased the fluid containing the precipitate thrown upon a filter. The fine powder is then washed and dried, sifted through fine lawn, to separate the finest particles for use, and mixed with the casein as required. The resulting liquid may have a second portion of tin salt added to it, and be again subjected to the action of the sheets of zinc. Another mode of producing argentine and bronze styles is to print on the fabric with a mixture of tho solution of silver, lead, bismuth, or other easily reducible metal with some reducing agent, such on aldehyde, methyl, alcohol, sodium hyposulphite, etc., thickened with glucose. A design is thus produced in the reduced metal. These metals arc affected more or less, however, by the fumes of sulphur. Gold and aluminum are free front this objection; but the former is too costly and the latter too difficult of application to render their use general for this purpose.

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