Assertion: black coloring material | /r/HasAspect | fiber
Facets:
Source sentences:
text: The amount of naphthoquinone derivative used is at least 1% by weight, preferably at least 5% by weight, relative to the material to be stained, but an amount of less than 1% by weight can be used by repeating the staining process to obtain a black coloring material having a low color value, or a fiber stained to a low color value.