Chapter 35 covers protein substances, modified starches, glues, and enzymes. This chapter includes adhesives based on natural or synthetic polymers, as well as protein substances and enzymes not elsewhere specified. Adhesives are one of the core commodities of this chapter, widely used in industry, construction, packaging, and consumer goods. The headings of this chapter are divided by base material type, such as animal glue, vegetable glue, rubber adhesive, plastic adhesive, etc., with 3506 covering other adhesives not elsewhere specified. Heading 3506 covers adhesives not specified in other headings, including adhesives based on polymers such as rubber, plastics (including synthetic resins), and silicones, as well as adhesives in retail packaging. This heading is further divided into subheadings by base material type and packaging form, such as 3506.10 for adhesives in retail packaging not exceeding 1 kg, and 3506.91 for other adhesives based on polymers. The first 2 digits 35 represent Chapter 35, covering protein substances, modified starches, glues, and enzymes. The 3rd-4th digits 06 represent heading 3506, i.e., other adhesives and adhesive products not elsewhere specified. The 5th-6th digits 91 represent subheading 3506.91, specifically referring to adhesives based on polymers (such as synthetic resins, rubber, silicones, etc.), but excluding adhesives in retail packaging with a net weight not exceeding 1 kg per unit (classified under 3506.10). Therefore, 350691 precisely covers industrial-use, non-retail-packaged polymer-based adhesives. This commodity is an adhesive based on polymers and is not classified under other more specific headings (such as 3501 protein glue, 3502 vegetable glue, 3503 animal glue, etc.). At the same time, it does not meet the retail packaging condition of 3506.10 (net weight per unit ≤ 1 kg), so it is classified under 3506.91. If it were in retail packaging, it should be classified under 3506.10.

Product Name: The specific name of the declared commodity, such as 'epoxy resin adhesive', 'polyurethane adhesive'. It should accurately reflect the base material and use. Use: Describe the main application areas of the adhesive, such as 'for wood bonding', 'for automotive assembly', 'for electronic component fixation'. Base Material Composition: Indicate the main polymer components, such as epoxy resin, polyurethane, acrylate, silicone, etc., and specify the content. Packaging Specifications: Indicate the packaging form and net weight, such as 'drum, 20kg/drum', 'tube, 50g/tube'. Appearance: Describe the physical state of the product, such as liquid, paste, solid, powder, etc. Brand: Declare the brand name (if any); if no brand, indicate 'no brand'. Model: Declare the product model or specification code for easy identification. Is it retail packaging: Clearly indicate whether it is retail packaging; if retail packaging, indicate whether the net weight per unit is ≤ 1 kg. Product Name: Epoxy resin adhesive; Use: For bonding metal and plastic; Base Material Composition: Epoxy resin 60%, curing agent 30%, filler 10%; Packaging Specifications: Iron drum, net weight 25kg/drum; Appearance: Gray paste; Brand: ABC; Model: EP-200; Is it retail packaging: No. Not indicating the polymer base material type, making it impossible to determine the subheading. Mistakenly declaring retail packaging (≤1kg) as non-retail packaging, incorrectly classified under 3506.91. False declaration of ingredient content, affecting classification and valuation. Ignoring the appearance description, which may affect commodity identification.

The core basis for classification is: 1) whether the commodity is an adhesive; 2) whether the base material is a polymer (synthetic resin, rubber, etc.); 3) whether it is retail packaging with a net weight per unit ≤ 1 kg. If it meets the polymer base material and is non-retail packaging (or retail packaging but net weight > 1 kg), it is classified under 3506.91; if it is retail packaging with net weight ≤ 1 kg, it is classified under 3506.10. In addition, adhesives specifically named in other headings, such as 3501 to 3505, must be excluded. 350610 Adhesives in retail packaging, net weight per unit ≤ 1 kg: 3506.10 covers all adhesives in retail packaging with net weight ≤ 1 kg, regardless of base material type; while 3506.91 only covers polymer-based adhesives in non-retail packaging or retail packaging but with net weight > 1 kg. 350691 Other adhesives based on polymers: The difference from 3506.10 lies in the packaging specifications; the difference from 3506.99 lies in the base material type: 3506.99 covers adhesives with other base materials (such as natural resins, silicates, etc.). 350699 Other adhesives not elsewhere specified: 3506.99 covers other adhesives not elsewhere specified, such as adhesives based on natural resins, shellac, asphalt, etc., while 3506.91 specifically refers to polymer base materials. 350520 Glues based on starches, dextrins or other modified starches: 3505.20 specifically refers to starch-based adhesives, which belong to Chapter 35 but are listed separately and not classified under 3506. 321410 Caulking compounds, mastics, resin cements, etc.: 3214.10 covers caulking compounds, mastics, etc., mainly used for filling and sealing rather than bonding; if a product has both bonding and sealing functions, it must be judged based on the main use. Confirm whether the commodity is an adhesive, not a sealant or mastic. Confirm whether the base material is a polymer (synthetic resin, rubber, etc.). Confirm whether the packaging is retail packaging and whether the net weight per unit is ≤ 1 kg. Confirm whether it belongs to adhesives already named in other headings (such as 3501-3505). Confirm whether the ingredient content is accurate to avoid classification errors caused by false declaration of ingredients.

How to determine whether an adhesive belongs to 3506.91? First confirm that the commodity is an adhesive and the base material is a polymer (such as epoxy resin, polyurethane, acrylate, etc.). Second, confirm that the packaging is non-retail packaging, or although it is retail packaging, the net weight per unit exceeds 1 kg. If so, it is classified under 3506.91. If it is retail packaging with net weight ≤ 1 kg, it is classified under 3506.10. What is the main difference between 3506.91 and 3506.10? The main difference lies in the packaging specifications: 3506.10 applies to adhesives in retail packaging with a net weight per unit not exceeding 1 kg, regardless of base material type; 3506.91 applies to polymer-based adhesives in non-retail packaging or retail packaging but with a net weight per unit exceeding 1 kg. Therefore, packaging specifications are the key to distinguishing the two. If an adhesive is based on natural rubber, which code should it be classified under? Natural rubber is a polymer, so an adhesive based on natural rubber, if it does not meet the retail packaging conditions of 3506.10, should be classified under 3506.91. However, note that if a natural rubber adhesive meets the specific naming of 3501 (protein glue) or 3502 (vegetable glue), etc., it should be classified under those headings first. How should 'Base Material Composition' be filled in the declaration elements during customs declaration? The chemical name and content percentage of the main polymer should be indicated, for example, 'epoxy resin 60%, curing agent 30%, filler 10%'. Avoid writing only 'synthetic resin' or 'polymer', because different polymers may affect classification. At the same time, if volatile components such as solvents are contained, they should also be briefly described. If an adhesive is used for electronic components, will it affect classification? Use generally does not affect classification, unless the use makes the product a part specifically for a certain device under another heading. For example, if an adhesive is a dedicated bonding agent for electronic components and is declared together with the components, it may be classified as a component. However, adhesives declared separately are still classified under 3506. How to inquire about the import tariff rate for 3506.91? The import tariff rate must be inquired according to the customs tariff of the destination country. For example, for China Customs, you can consult the 'Import and Export Tariff of the People's Republic of China', or inquire through the General Administration of Customs website or the single window. The tariff rate may vary depending on trade agreements, country of origin, and other factors; it is recommended to refer to the latest tariff. If an adhesive is in two-component packaging, how should it be classified? Two-component adhesives are usually packaged separately but declared as a set. If each component is a polymer base material and the whole is used as an adhesive, it is generally classified as an adhesive under 3506.91 (if non-retail packaging). However, if the components need to be mixed before use and the mixture is an adhesive, it is still classified as an adhesive. How to distinguish 3506.91 from 3214.10? 3506.91 is an adhesive, mainly used for bonding; 3214.10 is caulking compounds, mastics, etc., mainly used for filling and sealing. If the main function of the product is bonding, it is classified under 3506.91; if the main function is sealing and filling, it is classified under 3214.10. If it has both functions, it must be judged based on the main use.