Antimicrobial protection in the post-tanning process for leather by incorporating a biocide composition and a luminescent additive

An antimicrobial protection in the post-tanning process for leather by incorporating a biocide composition and a luminescent additive, wherein in the leather post-tanning step, a biocide composition is incorporated in an amount between 0.1% and 5% of the weight of the material to be tanned, the biocide composition comprises:

• between 3% and 5% of silver phosphate glass;
• between 1% and 3.5% of silicone;
• between 0.1% and 0.30% of aliphatic hydrocarbons;
• between 90% and 95% of water, and a luminescent additive that is added in an amount between 0.1% and 5% of the weight of the material to be tanned and comprises between 20% and 40% silica;
• alumina in a proportion between 10% and 30%;
• between 30% and 50% of calcium fluoride;
• between 0.5% and 3% of erbium (III) fluoride;
• between 5% and 15% of ytterbium (III) fluoride;
• a maximum of 5% of thulium (III) fluoride;
• and a maximum of 5% of europium (III) fluoride, with respect to the total weight of the luminescent additive.