9902.11.75 - Iminidiacetic acid ion-exchange resin (sodium 2,2'-[(4-vinylbenzyl)imino]diacetate - 1,4-divinylbenzene (2:1:1) (CAS no. 70660-50-3) in spherical beads with a mean particle size between 0.425 and 1.20 mm (provided for in subheading 3914.00.60)

This HTS category, 9902.11.75, specifically covers ion-exchange resin in the form of spherical beads, identified as iminodiacetic acid resin. The chemical composition is precisely defined as sodium 2,2'-[(4-vinylbenzyl)imino]diacetate - 1,4-divinylbenzene (2:1:1), with a CAS number of 70660-50-3. The physical form is critical: it must be in spherical beads with a mean particle size ranging from 0.425 to 1.20 mm. This precise specification ensures accurate classification for trade purposes.

The context of Section XXII and Chapter 99 indicates that this classification pertains to temporary legislation, modifications, or additional import restrictions, often related to trade agreements or specific agricultural adjustments. Unlike the broad agricultural and animal categories found at the HTS Database Root level (e.g., Chapter 01), this entry is highly specific, focusing on a specialized chemical product rather than general commodities. The reference to subheading 3914.00.60 further places it within the broader HTS framework for ion-exchangers based on natural polymers or synthetic polymers.

As this is a leaf node, there are no further subcategories. The classification relies entirely on the precise description of the chemical composition and physical characteristics of the ion-exchange resin. For practical classification, importers and exporters must verify that the product precisely matches the stated chemical identity and the specified particle size range for spherical beads. Any deviation in these parameters may necessitate reclassification.