A useful cyanoacrylate quality control program connects the batch, the package, the process, and the customer test. A clear appearance is only one observation. TongLin Adhesive recommends checking the supplied grade under a defined method and keeping a traceable record for every approved lot.
What to check before approving a batch
| Control point | What to compare | Why it matters |
|---|---|---|
| Identity and batch | Product code, lot number, production date, and sample record | Prevents a result from being assigned to the wrong material |
| Viscosity | Measured result against the agreed specification or technical data | Influences wetting, dispensing, and the delivered dose |
| Cure behavior | Fixture time under the same surface, gap, temperature, and test method | Makes a cure comparison meaningful |
| Appearance and package | Clarity or color, container condition, seal, label, and leakage | Finds packaging or handling problems before shipment |
| Documentation | Technical data, safety information, storage guidance, and change record | Gives the customer a usable approval file |
Use the product range to define the right comparison. For example, S505 M is listed in the low-viscosity 1.8–5 mPa·s range, S508 in the 30–50 mPa·s range, and CA-S1500 in the 1000–1500 mPa·s range. These products should not be judged against one shared viscosity target. Their listed reference cure times also differ: about 3 seconds for S505 M, 8 seconds for S508, and 25 seconds for CA-S1500 under the stated reference conditions.
A repeatable testing sequence
- Confirm the label, lot, container, and retained sample before opening the material.
- Record viscosity with the agreed instrument, temperature, and method.
- Test the adhesive on the actual substrates or an approved reference pair.
- Record dose, gap, alignment, fixture time, appearance, and the final test result.
- Repeat critical checks on retained samples or a second run when the application is sensitive to variation.
The test record should state its limitations. A fixture-time result is not the same as final joint performance, and a result on one plastic or metal does not prove suitability for every substrate. Surface preparation, gap, dose, and environment can all change the observed result.
Use QC records in OEM approval
For an OEM or private-label project, agree the acceptance points before production: product identity, package format, lot marking, sample quantity, test method, and document set. The cyanoacrylate OEM service can be reviewed alongside these requirements. This creates a practical quality file without claiming a certification that has not been independently verified.
Review the cyanoacrylate OEM production checklist and the storage and shelf-life guide. For a product-specific QC plan, send the substrates, package, and test requirements through Contact.