4811.10 - Tarred, bituminized or asphalted paper and paperboard:

Heading 4811.10 specifically classifies paper and paperboard that have been treated with tar, bitumen, or asphalt. This treatment imparts water-resistant, protective, or adhesive properties, commonly seen in roofing felt, road construction materials, or protective wrapping. The key distinguishing factor for this category is the presence of these bituminous or asphaltic coatings, which fundamentally alter the paper or paperboard's characteristics and intended use compared to other treated papers.

This category is distinct from its siblings. For instance, goods classified under 4811.60 are treated with waxes, paraffin, stearin, oil, or glycerol, offering different protective or functional qualities than bituminous coatings. Similarly, paper and paperboard coated or impregnated with plastics (excluding adhesives) fall under a different heading, as do gummed or adhesive papers. Heading 4811.10 is solely for materials specifically treated with tar, bitumen, or asphalt.

Subdivisions within 4811.10 exist to differentiate based on the physical presentation of the product. Subcategory 4811.10.11.00 applies to goods that are in specific large formats – either in strips or rolls exceeding 15 cm in width, or in rectangular sheets where one side exceeds 36 cm and the other exceeds 15 cm when unfolded. All other forms of tarred, bituminized, or asphalted paper and paperboard fall under the broader classification of 4811.10.21.00.