The effect of bottle thickness on sealing performance of PP cream jar

In the packaging industry, polypropylene (PP) cream bottles are widely recognized for their excellent performance and wide application. Sealing performance is a key factor in ensuring product quality and safety, and the thickness of the bottle body is one of the important parameters affecting the sealing performance, which is worth in-depth discussion.

Definition and importance of bottle body thickness
The bottle body thickness refers to the actual thickness of the bottle body material, usually measured in millimeters (mm). The bottle body thickness not only affects the appearance and feel of the bottle, but is also closely related to the structural strength, durability and sealing performance of the bottle. Reasonable design of the bottle body thickness can ensure the stability and safety of the product during use, especially in areas such as skin care products and cosmetics that have extremely high requirements for sealing.

Direct impact of bottle body thickness on sealing performance
Structural strength
The thickness of the bottle body directly determines its structural strength. A thicker bottle body can better maintain its shape and avoid deformation when subjected to external pressure (such as when the bottle cap is tightened). This deformation may cause poor contact between the bottle cap and the bottle body, thereby affecting the sealing effect. Relatively speaking, a bottle body that is too thin is prone to deformation when pressure is applied, which in turn leads to sealing failure.
Effectiveness of the sealing ring
Many PP cream bottles are designed with a sealing ring on the inside of the bottle cap to enhance the sealing effect between the bottle cap and the bottle body. The thickness of the bottle body should match the thickness of the sealing ring to ensure that the sealing ring can effectively fill the gap between the bottle cap and the bottle body when the bottle cap is tightened. If the bottle body is too thin, the sealing ring may not be able to fully play its role, thus affecting the overall sealing performance.
Stress distribution
The thickness of the bottle body also has an important influence on stress distribution. A thicker bottle body can more evenly disperse the pressure applied to the bottle body, reduce local stress concentration, and reduce the risk of material fatigue and deformation caused by stress concentration. This uniform stress distribution helps to maintain the stability of the sealing performance and ensure the reliability of the product during use.

Relationship between material properties and bottle body thickness
Physical properties of materials
Polypropylene (PP) material is known for its good flexibility and chemical resistance, and can maintain certain performance at different thicknesses. However, too thin materials may lead to insufficient strength, which affects the ability to withstand external pressure. Studies have shown that appropriately increasing the thickness of the bottle body can significantly improve the material's bearing capacity, thereby enhancing the sealing performance.
Thermal expansion characteristics
The material will expand thermally when the temperature changes, and changes in the thickness of the bottle will affect the thermal expansion characteristics of the material. A thicker bottle can better maintain its shape when the temperature changes, reducing the risk of seal failure due to thermal expansion. Therefore, when designing a PP cream bottle, the relationship between the thermal expansion characteristics of the material and the thickness of the bottle must be considered to ensure stable performance of the product under various environmental conditions.