Alum powder is traditionally used to size raw rice paper, reducing its absorbency and transforming it into Shou Xuan ("mature rice paper"), ideal for gongbi (elaborate-style) painting. Artists use alum-treated rice paper to precisely apply multiple color layers, maintaining crisp lines and sharp details without unwanted ink bleeding.
In addition to sizing paper, alum offers creative possibilities as a water-resistant masking agent. Applied selectively, alum solution creates unique resist effects, such as the delicate textures in Yu Zhixue-style ice landscapes or snowy, crystalline patterns. It acts similarly to masking fluid, allowing you to experiment with striking contrasts, textures, and clearly defined artistic elements.
Alum solution also protects your artwork during wet mounting, helping prevent bleeding of dark inks or heavy pigments. Simply brush a thin layer of alum water onto these areas prior to mounting for professional, clean results.
Weight: 10g
Usage Instructions:
For General Paper Sizing (making Shou Xuan):
- Dissolve alum powder in warm water at approximately a 1:20 ratio (alum to water).
- For typical use, approximately ½ teaspoon (0.5g) alum powder per 1 oz (30ml) of water is recommended.
- Apply solution evenly onto rice paper, and let it dry completely before painting.
As a Masking Agent for Creative Effects:
- Prepare alum solution (standard ratio or stronger, depending on desired effect).
- Apply selectively to areas of unsized rice paper you wish to mask.
- Allow to dry thoroughly before applying ink or color, creating distinctive textures such as snow effects, ice landscapes, or defined patterns.
Specialized Technique (Yu Zhixue-Style Ice Landscapes):
- Stir alum powder into hot water at a higher concentration (30g alum per 100ml water) until saturation (no further powder dissolves).
- Important: Avoid reheating or further dissolving, as overly thick solutions negatively affect artistic outcomes.
- Mix alum solution with ink and paint on the wrong ide of high quality unsized Xuan paper to produce icicle effect. See this video demo on YouTube.