All Glossary

Ceramic Transfer

A method for applying designs underglaze. Water-based colorants are silk-screened onto rice or tissue paper, dried, then the paper is applied, color-side-down, to a leather hard clay surface. Using a damp sponge and rib the paper is rubbed down and then peeled up to reveal the transfer. Designs can also be transferred to dry or bisque. Of course, if ware is going to be glazed the pigment must be designed as an underglaze.

Standard design transfers can be purchased online at many places. They are inexpensive and come with good instructions. Having custom transfers made can be complicated and expensive, the process is easy enough to merit silk screening your own. Commercial underglazes are not designed for this purpose, they are simply being force-fit to it. Formulating your own will produce a better-quality finished product (see below).

Related Information

An underglaze tissue transfer with clear overglaze at cone 6

This was applied at leather hard stage on Plainsman M370, bisque fired on, dipped in clear G2926B glaze, then fired at cone 6. The transfer was purchasing online and is made using the silky screening process. Since the pigment contains cobalt it does feather somewhat at the edges, this would be less of an issue at low temperature.

Ceramic tissue transfers: Good goat, better pig

These are whiteware mugs (Plainsman M370) with tissue transfer designs that were applied at the leather hard stage. The pieces were then dried, bisque firing, clear glazed and then fired to cone 6. Tissue transfers are sold online in a wide range of designs (in full color also). They can also be made at home by silk screening the appropriate type of ink onto the tissue paper (you can make your own ink using ceramic pigments). These overglaze transparent recipes are G2934 matte (left) and G2926B glossy (right). The matte glaze softens the edges of the design. The pig is a good demonstration of how crisp the edges of lines can be (once the application techniques are mastered). This method of decorating is far less expensive than decals. And does not require an extra firing. While the ink is somewhat powdery, it can be stabilized with spray starch if pieces need to be transported for firing.

Not to be ignored are the two transparent glazes. Control of thickness is important. Too thick and they will go cloudy. Too think and they won't fire smooth. For use as a dipping glaze the slurry should be thixotropic. Using them as a brushing glaze, while taking longer to apply, does enable tighter control of thickness.

When a DIY black underglaze makes sense

Black brushwork needs to go on thick enough in one brushstroke. Commercial products we have don't do that - thus my motivation to work on this. Another issue is that they try to cover too wide a firing range (thus they melt too much at the high end and not enough at the low end). I am experimenting on cone 6 Polar Ice porcelain jiggered bowls using G2926B dipping glaze. The base underglaze recipe here is a 90:10 MNP:nepheline syenite mix (you could use your own porcelain instead of MNP and feldspar instead of nepheline). To that, I add 15% black stain, 1.5% CMC gum and 5% bentonite. With the CMC gum and bentonite, and blender mixing, a brushable consistency that stays put can be achieved at a fairly low water content compared to commercial products (enabling it to go on thicker in a single brush stroke). Assuming application at leather hard state, the drying and firing shrinkage can be matched to the body by varying the plasticity of the porcelain used (e.g. the percentage of bentonite it contains). And the percentage of stain can be tuned for enough color but no bleeding, bubble clouding or crystallization. And we can adjust the degree of maturity by varying the proportions of MNP and Nepheline (commercial underglazes often melt too much by cone 6 and fade and diffuse as a result), this one stays opaque black.

Underglazes suitable for making silk screen transfers are another special case. The ideal one needs to cover well like this one. But it also needs to gel and harden enough to hang onto the paper but not so hard that it does not separate and transfer to the ware. Commercial products for brushing are unlikely to be optimal so it makes sense to mix your own and experiment with different amounts of gum.

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