Effect of histological feature of leather on acrylic resin retanning was written by Song, Ying;Zeng, Yunhang;Shi, Bi. And the article was included in Journal of the Society of Leather Technologists and Chemists in 2018.Safety of 5-Amino-3′,6′-dihydroxy-3H-spiro[isobenzofuran-1,9′-xanthen]-3-one This article mentions the following:
The effect of histol. features of leather on acrylic resin retanning was investigated by retanning pigskin, cattle hide and sheepskin leathers with fluorescein-labeled poly(acrylic acid) (PAA). A deeper penetration and a higher uptake rate of PAA were observed in the belly area of pigskin leather compared to in its butt area. This led to a greater increase in leather thickness of the belly. As for cattle hide and sheepskin leathers whose structural difference in various parts is not obvious, the differences in penetration and uptake of PAA and increase in leather thickness between their butts and their bellies were relatively slight. These results indicated that acrylic resins penetrate and fill the thinner and looser parts of the leather more easily. This fact gives acrylic resins a good selective filling property and is helpful to level out the structure of leather. In the experiment, the researchers used many compounds, for example, 5-Amino-3′,6′-dihydroxy-3H-spiro[isobenzofuran-1,9′-xanthen]-3-one (cas: 3326-34-9Safety of 5-Amino-3′,6′-dihydroxy-3H-spiro[isobenzofuran-1,9′-xanthen]-3-one).
5-Amino-3′,6′-dihydroxy-3H-spiro[isobenzofuran-1,9′-xanthen]-3-one (cas: 3326-34-9) belongs to benzofurans derivatives. Benzofurans are compounds with a planar structure having 10 pi electrons that include the lone pair on oxygen atom, which makes it more susceptible to electrophilic attack. Substituted benzofurans find applications such as fluorescent sensors, oxidants, in drug discovery, and in another field of chemistry and agriculture.Safety of 5-Amino-3′,6′-dihydroxy-3H-spiro[isobenzofuran-1,9′-xanthen]-3-one
Referemce:
Benzofuran – Wikipedia,
Benzofuran | C8H6O – PubChem