Transferring Techniques

Three different techniques were used to apply decals: water release, cement mounting, or a pressure sensitive process, used mostly for porcelain decoration.

The water-released decals were the most common type, and were divided into three subtypes: the water slide-off type — as implied by the name, the image was printed right side up and slid off the paper onto a surface face up; direct transfers, which required a light coat of varnish to be applied over the image and then placed in direct contact with the receiving surface; and, double purpose transfers, usually applied on glass and read from either side. The water-released direct transfers were printed on simplex paper. Originally, the entire decal was saturated before transfer. When the decal was placed in water, the mixture of gelatine, albumen and gum arabic separated from the paper and floated on the water.

A transferred monogram placed on the Royal Train during the 1939 Royal Tour of Canada (CSTM/CN Collection 003710)

The decal was carefully lifted, pressed on the transferring surface and left to dry. The transferred image was always covered with lacquer or varnish to enhance its durability.

Because the image could easily be damaged when lifted from the water, a safer technique was eventually developed. First the transferring surface was cleaned of dust and dirt. Then the surface of the image was painted with a thin coat of varnish and left to dry. Just before transferring, the image was painted with another layer of varnish and the entire transfer, including the backing sheet, was pressed onto a surface, from the centre toward the edges. When the decal was firmly attached to the surface, the paper layer was slowly saturated with water. This process required precision in order to prevent the water from soaking through to the image layer. The soaked backing paper was then detached from the design.

A duplex transfer with the monogram of King George VI (750129.388)

The water-released transfers prepared on the duplex paper required a cement mounting technique. A small area of tissue, usually at the corner, was first separated from the backing paper. The image was then coated with decal cement applied with a soft cloth and left to set for about ten minutes. When the cement reached a very specific thickness, the decal was pressed to a clean wet surface and rolled down with a rubber roller or sponge. The wet surface prevented the decal from attaching immediately and made it easier to position the transfer.

The backing paper was peeled away starting with the loose corner. The tissue paper and some gum arabic deposit would remain on the design and had to be removed with a wet sponge. If these remnants were allowed to dry, they would crack the transfer, damaging the image. The affixed transfer was allowed to dry for up to two weeks before being washed with benzine to remove surplus cement. The final image was protected with a coat of varnish.