Troubleshooting

Understanding and addressing common issues with domed labels can help ensure a high-quality finish. There are two main types of bubbles that can occur: O₂ (air) and CO₂ (carbon dioxide).

O₂ bubbles are a common issue that usually occurs at the start or finish of using a new cartridge and mixer.

• At the start, bubbles occur as the resin fills the air pockets in the mixer to “wet” it out. At the end, bubbles collect at the bottom of the emptying cartridge.
• O₂ bubbles are clearly visible immediately after resin application when the material is still fluid.
• Warming the surface with a flame gun will effectively eliminate these bubbles. Many customers use the same mixer (if they work quickly) to avoid air bubbles at the start of a new mix.

CO₂ bubbles form due to moisture sensitivity in polyurethane resins, and they typically appear about an hour after resin application.

• Due to the chemical composition of polyurethane resins, they are moisture-sensitive. If moisture is introduced during the initial curing stage, CO₂ gas bubbles will form about an hour after resin application.

Several factors can introduce moisture contamination, which is a leading cause of CO₂ bubbles.

• Production Environment: The environment must be warm, dry (with the lowest possible humidity), and dust-free.
• Print Material: If the print material is coated and printed using a water-based inkjet printer, it will contain moisture. This must be dried off, or the material/ink might not be compatible with fast-curing polyurethane resin.
• Vinyl Printing: When printing on vinyl using eco or solvent inks, ensure they are fully degassed before applying the resin.
• Resin Cartridge: Moisture contamination inside the resin cartridge is unlikely due to our production filling process. To test, apply resin to a neutral surface like glass, which cannot contain moisture. If no bubbles appear after curing, the moisture likely comes from the production environment or the printed doming material, vinyl, or ink print process.

For further assistance, please provide details about your production process, and we can offer more specific advice. For additional support, please email support@liquid-lens.com.