HS Code for UPR resin

Unsaturated Polyester Resin (UPR) is classified under HS code 3907.91. This classification falls within Chapter 39, which covers plastics and articles thereof. Heading 3907 includes polyacetals, other polyethers, and epoxide resins, in primary forms, as well as polycarbonates, alkyd resins, and other polyesters. Subheading 3907.91 is specifically designated for "unsaturated" polyesters. UPR is a thermosetting resin characterized by the presence of double bonds in its polymer chain, allowing it to cross-link with monomers like styrene. To be classified under this code, the resin must be in a "primary form," which includes liquids, pastes, blocks, lumps, or powders, as defined by Note 6 to Chapter 39.

Products Included

• Orthophthalic unsaturated polyester resins
• Isophthalic unsaturated polyester resins
• Dicyclopentadiene (DCPD) resins
• Bisphenol A fumarate resins
• Vinyl ester resins (often classified here due to chemical similarity)

Common Misclassification

UPR is frequently misclassified under HS code 3907.99, which is the residual category for "saturated" polyesters. The presence of unsaturation (double bonds) is the critical technical factor that mandates 3907.91. Another common error involves HS code 3208; if the resin is dissolved in a volatile organic solvent and the solvent exceeds 50% of the weight of the solution, it may be classified as a paint or varnish under 3208 rather than a resin in primary form.

FAQ

What is the HS code for UPR resin?

The HS code for unsaturated polyester resin in primary form is 3907.91.

What qualifies as a primary form for UPR?

Primary forms include liquids and pastes (including dispersions and solutions) or irregular shapes such as granules, flakes, and powders, provided they have not been further processed into finished articles.