To provide a natural protein fiber product which has an excellent transfer printing dyeing function and which can be easily dyed with transfer printing via a transfer paper.
A natural protein fiber product with an enhanced dyeing function is obtained by subjecting a natural protein fiber product to graft processing by using a graft monomer including at least one compound selected from: an acrylic acid derivative or a methacrylic acid derivative including a phosphate group; a vinyl compound having an alkoxy group which is a monovalent functional group; or a vinyl compound having a fluorine chain as a side chain, or by subjecting the natural protein fiber product to graft processing by using a graft monomer including a mixture of styrene and polyethyleneglycol dimethacrylate, or polyethyleneglycol dimethacrylate. When a rate of graft processing is 30%, strength and elongation of silk yarn before and after transfer printing dyeing processing are not significantly different from those of an unprocessed sample, and the graft-processed product has moderate light resistance.
HIRATA YUICHI
HAMADA KUNIHIRO
