1. Classification by Bottle Material: Glass, Plastic, Metal Glass dropper bottles: Their primary advantage is their chemical inertness, meaning they won't react with the contents. They're ideal for storing active ingredients (such as vitamin C serums and retinol serums) or corrosive liquids (essential oils and pharmaceutical solvents). Clear glass dropper bottles: Suitable for products that don't require light protection (such as regular toners and serums), making it easier to see how much is left. Dark glass dropper bottles (amber, cobalt blue): With built-in UV protection, they effectively block UV rays, preventing oxidation and deterioration of ingredients, making them the best choice for light-sensitive products. Plastic dropper bottles: Their primary advantages are lightness, drop resistance, and low cost, making them suitable for daily use and various office settings. However, care should be taken with the material to avoid chemical intrusion. PP dropper bottles: They offer excel...

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...