How to Determine if a Paint Can Has Been Opened

✅ 1. Check the Sealing of the Can Lid

Original Unopened: The seam between the lid and the can body has a complete, one-time sealing film or indentation, with no prying, scratches, or signs of secondary pressing.

Signs of Opening: Pry marks, paint peeling, deformation on the edge of the lid, or a damaged or missing sealing film; some products have an anti-counterfeiting ring on the inside of the lid, which, if broken, indicates that it has been opened.

Tip: High-end latex paints (such as Dulux and Nippon) usually have smooth, undamaged edges on the lid. If rust, indentations, or glue residue are found, it is very likely that a genuine can has been recycled and refilled with counterfeit paint.

✅ 2. Observe the Anti-counterfeiting Label and QR Code
Reputable brands will have an anti-counterfeiting label on the can body or lid, containing an anti-counterfeiting code that can be scratched off for verification.

Scan the QR code with your mobile phone or enter the anti-counterfeiting code. If it displays "First Query" or "Query Count is 0," it can generally be determined that the can is unopened.

If you receive a message saying "Checked multiple times" or "Not genuine," the product may have been used or tampered with.

Note: Some counterfeiters copy anti-counterfeiting information. It is recommended to verify through the official website or official WeChat account, not third-party links.

✅ 3. Check if the inkjet code and steel stamp are aligned. Most legitimate paint cans have laser-printed codes at the junction of the lid and body, and the codes should be continuous and aligned.

If you find the codes are discontinuous, blurry, or misaligned, it means the lid has been opened and resealed.

Some brands also have a unique numerical steel stamp inside the lid, matching the can's serial number; damaging it renders the product invalid.

✅ 4. Check the condition of the protective layer and liquid level inside the can. After opening the lid, observe whether there is an intact oxide film or plastic sealing layer inside.

Unopened latex paint should have a complete protective film on the surface. After peeling it off, the paint surface should be smooth, without any dried skin or delamination.

If you see a hardened paint layer, severe separation, or an unusual odor upon opening, it indicates that the paint has been exposed to air for a long time and may have been opened prematurely.

Friendly reminder: A small amount of emulsion may separate after opening a can of high-quality latex paint. This is normal and does not indicate spoilage or that the can has been opened prematurely.

✅ 5. Inspecting the goods on the spot is the safest approach. It is recommended to purchase from authorized online stores or reputable building materials markets and open and inspect the can on the spot after payment.

Keep the empty can until the construction is completed to prevent it from being switched during the process.