染め粉 is read as そめこ (someko) and means dye.
そめこ
someko
せんしょく
dyed colour (color)
そめる
to dye
そまる
to be dyed
しみる
to feel keenly
しみ
spot (on one's skin, e.g. chloasma, liver spot)
せんしょくたい
chromosome
そめ
dyeing
せんりょう
dyes
そまりぐあい
effect of dyeing
dyeing and weaving
しみこむ
to soak into
せんしょくぶんたい
chromatid