Cosmetic bottle mold

Appearance and Structure

• The mold is a precisely engineered and often complex structure. The mold base, which can be made from high-quality alloy steel such as P20 or 718H, or aluminum alloy like 6061 - T6 or 7075 - T6, provides a stable and rigid foundation. It houses the cavities and cores, which are crafted from specialized plastic mold steel like H13 or S136. These cavities and cores are intricately designed to create the unique and often aesthetically pleasing shapes of cosmetic bottles, including details such as curves, embossments, and smooth transitions.

• It may also incorporate features like cooling channels, which are carefully laid out to ensure even heat dissipation during the molding process. This helps in controlling the solidification rate of the plastic and minimizing defects like warping or sink marks.

Functionality

• The primary function of this mold is to transform molten plastic into high-quality cosmetic bottles with excellent dimensional precision. The dimensional accuracy ranges from ±0.03 to ±0.1mm, which is vital for ensuring proper fit and function of bottle closures, pumps, and other accessories.

• The surface roughness of the mold plays a significant role in determining the final appearance of the cosmetic bottle. For the exterior cosmetic surfaces that are visible to consumers, a surface roughness of Ra0.2 - Ra0.8μm is typically maintained to achieve a smooth and glossy finish. The internal surfaces, which have less stringent cosmetic requirements but still need to ensure proper flow and dispensing of the cosmetic product, have a surface roughness of Ra0.4 - Ra1.2μm.

• The ejection system, whether it is a mechanical one with ejector pins and sleeves or a pneumatic ejection system, is designed to gently and efficiently remove the molded bottle from the cavity once the plastic has cooled and solidified. This helps in preventing any damage to the delicate bottle structure and maintaining its integrity.

Material and Durability

• The selection of materials for the mold base and cavity/core is based on their ability to withstand the rigors of the molding process. The alloy steel or aluminum alloy base materials offer strength and stability, while the specialized plastic mold steel for the cavities and cores can endure the high pressures and temperatures associated with injection molding. This enables the mold to have an expected service life of producing 300,000 to 1,000,000 parts.

• To ensure the longevity and consistent performance of the mold, a recommended maintenance cycle is in place. After every 10,000 to 30,000 molding cycles, the mold undergoes maintenance procedures. This includes inspection for any signs of wear or damage, cleaning of the cavities and cooling channels to remove any residue or debris, and replacement of any worn-out components such as ejector pins or seals.