Also, the makeshift ink can damage the skin, cause permanent scarring, or contain harmful chemicals.
When printing color images by combining multiple colors of inks, the colored inks usually do not contain much image detail.
When chemical analysis suggested the ink contained a 20th century synthetic version of titanium dioxide, the map was denounced as a fraud.
The erasable ink does not contain the toxic chemical compounds xylene and/or toluene as have been used in permanent markers.
The inks used contain phosphors which cause them to glow when exposed to the ultraviolet light emitted from black lights.
Several tests were carried out to find out whether the ink contained chloroacetamide, a preservative, in an effort to definitively date the ink.
The materials can't be recycled and the inks frequently contain heavy metals.
The erasable ink does not contain the toxic chemical compounds xylene and/or toluene, unlike permanent markers.
And the ink contains the dyes and minerals in the exact proportions used by first century scribes.
A. Though the inks used in glossy magazines can contain heavy metals, those used to create newspapers are generally nontoxic.
