PURPOSE: To obtain the titled inexpensive binder for steel casting especially having improved heat resistance, by blending lignin and methylol urea resin or methylol phenolic resin with furfuryl alcohol without lowering self-curing properties.
CONSTITUTION: 20W15wt% high-purity highly reactive lignin powder and 20W 35wt% methylol urea resin or methylol phenolic resin as a polyfunctional methylol compound are blended and dissolved in 30W60wt% furfuryl alcohol. For steel casting methylol phenolic resin is blended, and for cast iron methylol urea resin is blended. The reduction in expensive furfuryl alcohol and the use of lignin as its substitute can make the binder inexpensive. It is curable at normal temperature by the addition of an acidic curing agent.
FURUYA NOBORU
HIROSHIGE TOSHITAKA
INOUE MASANORI
