From surface smoothness to pump head compatibility, we control quality across two dimensions.

I. Appearance Quality

Surface Smoothness: glass bottle bodies must be free of scratches, bubbles, pinholes, uneven shrinkage, and other defects. Even minute surface bubbles may harbor dirt or foster bacterial growth (posing significant risks for skincare and food products). We ensure uniform surface smoothness through a combination of visual inspection under natural light and tactile verification.

Color Consistency: Colors must closely match the color swatch or Pantone number confirmed by the customer, with no visually discernible color variation permitted within the same batch. This requires suppliers to possess advanced color matching systems and stable masterbatch addition processes.

Printing Durability: For screen printing, foil stamping, labeling, etc. Inspection should focus on print clarity, with particular emphasis on testing print adhesion and wear resistance. Common tests include the “tape peel test” (applying 3M tape and peeling it off to check for ink transfer) and the “abrasion test” (rubbing the printed surface over 50 times with a soft cloth to ensure no fading).

II. Size Compatibility

Bottle Dimensions: Measure critical dimensions such as the outer diameter of the bottle opening, height, and wall thickness using tools like calipers and projectors to ensure they fall within the tolerances specified in the drawings.

Fit between cap and bottle: The diameter, thread pitch, and height of the bottle neck must perfectly match the cap. Manual assembly testing verifies that the cap twists on smoothly without binding, neither too loose nor too tight. For flip-top caps, hinge operation must be tested over 100 times to ensure no risk of breakage.

Pump Head/Spray Nozzle Fit with Bottle Opening: For injection-molded bottles equipped with pump heads (e.g., lotion glass bottles) or spray nozzles (e.g., spray glass bottles), the inner diameter of the bottle opening and the flatness of the opening surface are critical. Dimensional deviations may cause pump head clogging or uneven dispensing. After assembling the pump head/spray nozzle onto the bottle, we conduct over 20 dispensing tests to ensure smooth operation.