FUNORI: OVERVIEW OF A 300-YEAR-OLD CONSOLIDANT
JOSEPH R. SWIDER, & MARTHA SMITH
4 USES OF FUNORI IN CONSERVATION
The same flexibility applies to the ways in which funori is used, normally for applications that require a low-strength consolidant, usually on paper. The advantages of funori as a consolidant are many: it has good penetrating ability and wets surfaces easily, dries matte, can be diluted with water, and is nontoxic. Uses for funori in conservation include sizing paper and textiles; consolidating flaking and powdering paint; repairing and facing East Asian painting and works on paper (Keyes 1986; Smith 1990); repairing silver and gold leaf and mica (Higuchi 1979; Kariya 1995); backing paintings when mixed with animal glue (Oka 1988); and repairing the structure of wooden objects (Tsujimoto 1979). In Japan it has been used to adhere tiles and paper to walls and as a cement in plaster wall construction and in porcelain decoration. Most authors note the advantages of funori as a low-strength consolidant with low surface tension and low gloss (Higuchi 1979; Michel et al. 2002). One study has examined its effects over time with artificial aging (Michel et al. 2002). This study examined changes in gloss, color, and mechanical strength of funori that underwent a typical artificial aging regime of accelerated light, temperature, and humidity. The funori was shown to bleach more under the extreme light conditions, becoming slightly more brittle but still flexible. Although the artificial aging experiments are encouraging, we stress that the long history of funori-treated objects without note of its failure or discoloration is more creditable.
To confirm funori's properties, we have examined previously treated artwork in the Freer Gallery of Art, where funori is used in paper and East Asian painting conservation regularly. A concentrated solution of funori is made up and thinned to suit the treatment at hand. Often the funori is applied in thin layers until the treatment is complete. For consolidation, all that is required is funori added to the edges of flaking paint and the flakes held down to secure. We recently examined several objects treated between 1975 and 1980 and compared their present state to their original treatment records.
- Chinese wood sculpture, Southern Sung, acc. no. F1974.6: The entire surface was brushed with funori to consolidate flaking paint. It is noted that other portions of the statues required stronger consolidation on the wood base where losses were evident. In these cases Paraloid B-72 was employed.
- Japanese wood sculptures, Kamakura period (1185–1333):
- Acc. no. F1974.20: Funori was brushed over the entire surface of each figure in 1977 to consolidate flaking pigment and gilding. In 2002, funori was again used to consolidate some spots of lifting paint to be compatible with the earlier treatment. According to the records, the gilding did not respond to the funori treatment at this time and was treated with Paraloid B-72.
- Acc. no. F1977.19: The entire surface was brushed with funori to consolidate flaking paint and gold. It was noted in this treatment that areas that required more layers of funori could not be treated before the previous layer was dry. The gilding had to be held in place while drying.
- Acc. no. F1978.28: Funori was used on this object to consolidate powdery pigment and paint that was hanging on. A stronger consolidant was required for structural consolidation where funori was too weak. 2d. Acc. no. F1976.12: As with the other wooden statues, funori was originally used to consolidate the entire surface of the object-paint and gilding. Funori was applied again in 2002 prior to exhibition, but the gilding required Paraloid B-72 for consolidation where the funori was ineffective.
- Indian painting on textile, Mughal period, ca. 1570, acc. no. F1949.18: In 1977 a thin solution of funori was applied to much of the painting to consolidate the flaking paint, followed by a thicker solution on the white or pastel areas that were more likely to flake off with time. An additional funori treatment was required a month later, and no further treatment was required.
No color shifts were noted in the treatment records. Visual examination of the objects at the present time and comparison with previous photographs showed no color change. Funori continues to be used as a consolidant, adhesive, and poultice material, especially on Asian and Near Eastern works of art on paper.