The effect of bottle inner wall treatment on sealing performance of PP cream jar

In the modern packaging industry, PP cream bottles are widely used in skin care products, cosmetics and pharmaceuticals due to their lightness, durability and good chemical stability. However, sealing performance is one of the key factors to ensure product quality and safety, and the treatment of the inner wall of the bottle plays a vital role in sealing performance.

Definition of bottle inner wall treatment
The inner wall treatment of the bottle refers to a series of surface treatment processes performed on the inner wall of the bottle during the production process. These treatments can include cleaning, polishing, spraying, coating and other surface modification technologies. Through these treatments, the surface quality of the bottle can be improved, the friction between the liquid and the bottle wall can be reduced, and the sealing performance can be improved.

Methods for treating the inner wall of the bottle
Cleaning treatment
During the production process, the bottle may retain dirt, grease or chemicals from the production process, so cleaning is the first step in the inner wall treatment. Ultrasonic cleaning, chemical cleaning and other methods can effectively remove impurities on the inner wall to ensure the clean surface of the bottle.
Polishing treatment
Polishing treatment can significantly improve the smoothness of the inner wall of the bottle. Smooth inner wall can reduce the friction between liquid and bottle wall, reduce the risk of liquid retention, and thus reduce the failure of seal caused by bubbles or liquid residue.
Surface coating
In some cases, specific coatings can also be applied to the inner wall of the bottle to enhance its waterproof, oil-proof and corrosion-resistant properties. These coatings can not only improve the durability of the bottle, but also further improve the sealing performance.
Plasma treatment
Plasma treatment is an advanced surface modification technology that can form a thin film on the inner wall of the bottle to increase the hydrophilicity or hydrophobicity of its surface. This treatment can effectively change the fluidity of the liquid in the bottle, reduce the residue, and thus improve the sealing performance.

The effect of bottle inner wall treatment on sealing performance
Reduce liquid retention
The smoothness of the inner wall of the bottle has a direct impact on the fluidity of the liquid. The polished inner wall of the bottle can significantly reduce the retention of liquid and reduce the risk of sealing failure caused by liquid residue. Liquid retention may not only lead to changes in product ingredients, but also cause the growth of microorganisms, thereby affecting the safety of the product.
Improve the sealing effect
Good inner wall treatment can ensure a close fit between the bottle cap and the bottle body and enhance the sealing effect. The cleaned and polished bottle body can better cooperate with the sealing ring to ensure a good seal when the bottle cap is tightened. This sealing performance is essential to prevent the infiltration of air and moisture, especially in the packaging of skin care products and medicines.
Reduce chemical reactions
Some cosmetic and pharmaceutical ingredients are very sensitive to the container material, and the treatment of the inner wall of the bottle body can reduce the risk of chemical reactions. Through coating or other surface treatment, the contact between the liquid in the bottle and the bottle body material can be effectively isolated, reducing the deterioration or failure of the product caused by chemical reactions.
Improve durability
The inner wall of the bottle body that has been properly treated can improve its durability and reduce damage caused by friction or chemical corrosion. The durable bottle body can maintain good sealing performance during long-term use, ensuring the stability of the product during the shelf life.