Burning of a cotton fabric impregnated by synthetic zinc carbonate hydroxide as a flame retardant

Zinc carbonate hydroxide [ZnCO$_3$ $\cdot$ Zn(OH)$_2$] synthesized by means of the multiple-bath method was deposited onto a cotton fabric, and its uniformity was ensured by means of squeeze rolls. Prolonged burning was observed on treated specimens: 200.5 sec for 20.20% of ZnCO$_3$ $\cdot$ Zn(OH)$_2$ added to 100 g of a dry fabric increased to 337.5 sec for a 45.39% addition. The ashes of the treated specimens were subjected to X-ray diffraction analysis, and the result was compared with data for zinc and zinc-oxide powders. The existence of zinc oxide was detected in the ashes, but no traces of the metallic zinc were discovered. Therefore, it can plausibly be assumed that a reduction-oxidation reaction occurs during the smoldering process.