Contents change color or evaporate? Is the barrier property of the glass bottle not good enough? Many customers have reported problems such as discoloration, abnormal odor, and decreased concentration of skin care products during product sales or use. This is especially true for skin care formulas containing essential oils, active ingredients, or natural plant extracts. In other words, during product sales or daily use, consumers often report that skin care products have changed color; some products emit abnormal odors, which not only affects the user experience, but may also have an adverse effect on skin health; and some customers have found that the concentration has decreased after use, which undoubtedly reduces the effectiveness of the product.   Cause analysis These problems are often closely related to the poor light-blocking ability and airtightness of glass bottles. Although transparent glass has a good visual effect, it is easy for external factors such as ultraviolet ra...

1.Thickness measurement The precise thickness of each layer of a tube is fundamental to its performance. This test uses a micrometer or specialized thickness gauge to measure the actual thickness of each layer (from the inner barrier film to the outer printed layer), typically at five to ten points throughout the tube. The goal is to ensure compliance with design specifications. 2.Sealing performance test Heat Seal Strength (Tube End): Cosmetic Plastic Cream Tube ends are sealed using heat during the manufacturing process. This test measures the force required to tear the seal. It ensures that the seal will not crack during extrusion, transportation, and storage. Standards generally require a minimum strength to ensure reliability. Torque Test (Tube End to Cap): This test evaluates the tightness of the connection between the tube end and the cap. A torque meter measures the force required to unscrew or tighten the cap, ensuring it is neither too loose nor too tight....