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A product in the form of irregular, flat, brown, hard fragments (about 2 mm thick) or flakes, manufactured of (% by weight):
pine resin (also called tall oil rosin or rosin)
approx. 58-69,
maleic acid anhydride
approx. 1-4,
various phenols
approx. 11-24,
formaldehyde
approx. 5,5-9,
pentaerythritol
approx. 7-12.
The product results from a multi-step process starting with rosin and maleic anhydride being transformed into a rosin adduct. After the addition of magnesium oxide (as a catalyst for the subsequent reactions), phenols and formaldehyde a polymerised resin is formed. Finally, free acid groups of the resin are esterified after the addition of pentaerythritol.
The product at issue is used in the printing industry as an adhesive.
| 3909 40 00 |
Classification is determined by general rules 1, 3(a) and 6 for the interpretation of the Combined Nomenclature (CN) and the wording of CN codes 3909 and 3909 40 00.
Classification under heading 3506 as adhesives based on polymers of headings 3901 to 3913 is excluded by application of general rule 3(a) as the product is described more specifically in heading 3909.
In the manufacture of a rosin derivative, the rosin adduct is esterified with ethylene glycol, glycerol or another polyhydric alcohol (see also the Harmonized System Explanatory Notes to heading 3806 (D)(I)(7)). However, in the case of the product in question, before esterification with a polyhydric alcohol (pentaerythritol, in this case), a polymerisation reaction with phenol and formaldehyde takes place. Classification under heading 3806 as a derivative of rosin is therefore excluded.
The molecules of the polymerised intermediary product have a molecular weight of around 5 000-30 000 g/mol. Subsequently, the free acid groups are esterified through the addition of pentaerythritol and a cross-linking follows with an increase of molecular mass to about 100 000 g/mol. Consequently, the obtained product is a polymer of Chapter 39, which differs from the adducts and derivatives of the rosin of heading 3806 due to its high molecular mass.
The product is therefore to be classified in CN code 3909 40 00 as phenolic resins.
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