Application of precise sealing technology in airless bottles

1. High-precision injection molding and heat sealing technology
The joint between the bottle body and the bottle cap of airless bottles is the key to sealing performance. In order to ensure a tight connection between the bottle mouth and the bottle body, manufacturers usually use high-precision injection molding. This process ensures that the joint between the bottle body and the bottle cap is smooth and seamless, preventing air from penetrating into the bottle from the joint. The precision of the injection mold is crucial, and the design and processing accuracy of the mold directly affect the sealing effect of the bottle.

Heat sealing technology is also commonly used in the manufacturing process of airless bottles, especially for the joint between the bottle mouth and the bottle body. Heat sealing technology uses high temperature heating and pressure to make the connection between the bottle cap and the bottle body tighter and form a strong seal. The heat-sealed joint can not only effectively prevent air leakage, but also provide additional protection to prevent external contaminants from entering the bottle.

2. Rubber gasket or silicone seal ring
Airless bottles are usually equipped with rubber gaskets or silicone seal rings between the bottle mouth and the bottle cap, which can provide excellent sealing. The function of the sealing ring is to ensure that the bottle mouth can fit tightly when the bottle cap is closed to prevent air from entering the bottle. Rubber and silicone materials have strong elasticity and corrosion resistance, and can still maintain a good sealing effect in long-term use.

In terms of design, manufacturers usually choose sealing rings of different specifications according to different bottle types and bottle mouth sizes, and ensure that they can maintain stable sealing performance in various environments. For airless bottles with particularly high requirements, some manufacturers will also use double sealing technology, that is, two or more sealing rings are set between the bottle mouth and the bottle cap to further improve the sealing and anti-pollution effect.

3. Precision design of bottle mouth and nozzle
The design of the bottle mouth and nozzle of the airless bottle is very critical because this part directly involves the exposure of the product in the bottle. In order to prevent air backflow and keep the bottle sealed, manufacturers usually design a one-way valve or automatic back-sucking function. This design ensures that the bottle mouth will not inhale air due to external pressure or vibration during the use of the product in the bottle.

Some high-end airless bottles use an airtight valve design that opens only when the bottle body is pressed, allowing the product to flow out of the bottle mouth without causing air to enter due to changes in pressure inside the bottle. This precision design of the bottle mouth reduces the contact between the outside air and the contents of the bottle, preventing contaminants such as bacteria and dust from entering the bottle.

4. High barrier materials
The bottle body and bottle cap of the airless bottle are made of high barrier materials, which is a key sealing technology. High barrier materials usually have strong resistance to gas and moisture penetration, and can effectively isolate the entry of air, oxygen and moisture. Common high barrier materials include high-density polyethylene (HDPE), polyethylene terephthalate (PET), and some special glass materials.

These materials can ensure that the contents of the airless bottle will not oxidize or deteriorate due to air penetration during long-term use. Many high barrier materials are also UV-resistant, which can prevent UV damage to the contents of the bottle, especially in the field of cosmetics and skin care products, where UV damage to ingredients may cause product failure or premature deterioration.

5. Antimicrobial coating and aseptic production environment
To further ensure that the products in the airless bottles are not contaminated by the outside world, many manufacturers apply antimicrobial coatings to the inner wall of the bottles. These coatings are made of antimicrobial materials, which can effectively inhibit the growth of microorganisms and prevent bacteria from multiplying in the bottles. Antimicrobial coatings are often used for products that require higher hygiene standards, especially in the packaging of medicines and high-end skin care products.

When producing airless bottles, they are also carried out in clean workshops to avoid the entry of external pollutants such as dust and bacteria. The environment of the dust-free workshop can ensure that every link in the production process reduces the source of pollution as much as possible, ensuring the cleanliness and sealing performance of the final product.

6. Air tightness and sealing test
During the production of airless bottles, manufacturers usually conduct a series of rigorous tests to ensure that the sealing performance of the bottles meets the standards. Common testing methods include pressure testing, vacuum testing, and water sealing testing. These tests can check the sealing between the bottle body and the bottle cap to ensure that there is no air infiltration in the bottle.

The pressure test mainly checks whether there is any leakage in the bottle by simulating the pressure changes in the use environment; the vacuum test checks whether the bottle can maintain a vacuum state for a long time after the air is extracted from the bottle; the water seal test verifies the sealing of the bottle by testing the bottle immersed in water.