Mold inhibitor in Hardiebacker, DensArmor Plus, Wonderboard, and Purple Board (XP)?
All of these products… Hardiebacker, DensArmor Plus, Wonderboard, and Gold Bond XP (Purple Board) indicate that they inhibit mold growth, but I do not see any specific mold inhibitor listed on the SDS sheet. Does anyone know what the mold inhibitor is?
DensArmor Plus: http://msds.gp.com/msdsinternet/LatestMSDS.aspx?msdsid=6105&LangCode=E
Gold Bond XP (Purple): https://www.nationalgypsum.com/File/sds01003.pdf
Wonderboard: https://www.custombuildingproducts.com/media/61049158/wonderboardlite_ghs-whmis_english_31-august-2017_22.pdf
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Replies
Lime.
An MSDS is not always the best source of information on complete chemical content. "Trace" materials do not have to be listed and any proprietary ingredients don't have to be reported either.
See this interesting article on MSDS: https://www.buildinggreen.com/news-article/tale-two-material-safety-data-sheets-msds.
Gold Bond XP contains Sporgard which is apparently an "(Aqueous) dispersion of approx. 19 % thiabendazol, 19 % azoxystrobin and 1.9 % fludioxonil."
Who knows, the others might be much worse and not disclose it.