Composition of cosmetic glass bottles for creams

We often talk about cream-type cosmetics mainly including facial creams, eye creams, etc. The cosmetic glass bottles used to package these products are not quite the same as the glass bottles used to package lotion extracts. The glass bottles used for packaging cream products are generally shorter and fatter, mostly designed as wide-mouth bottles. In general, glass bottles for cream products have three main components, namely screw cap, gasket, and bottle body. We have already introduced in detail the processing process of the glass bottle body. As for the material of the glass bottle body, we will introduce it in another article. In this article, we will focus on the screw cap and gasket.

Here is the content list

• Screw caps for cosmetic glass bottles

• Gaskets for cosmetic glass bottles

Screw caps for cosmetic glass bottles

Cream bottles are usually made of glass, but screw caps are rarely made of glass. On the one hand, glass is fragile, and the screw cap is often removed, and because of its light quality, it is easy to be dropped by collision and has the potential to be broken. There are generally four kinds of materials for making cosmetic glass bottle caps, including PP material, ABS material, AS/MS material, and acrylic material.

PP material is polypropylene material, it has lower heat deflection temperature, lower transparency, lower gloss, and lower rigidity, but PP material has strong impact strength, and PP screw cap has good surface rigidity and scratch resistance characteristics. In addition, PP screw caps do not have the problem of cracking due to environmental stress.

ABS material has excellent impact resistance, heat resistance, low-temperature resistance, chemical resistance, and electrical properties, and also has easy processing, stable product size, good surface gloss, etc. The screw caps made of ABS material are easy to paint and color, and can also be sprayed with metal, plating, welding, and other processing procedures on the surface.

AS and MS materials have high transparency, and these two materials' naive grease, good printing performance, is to do transparent products of high-quality raw materials. The disadvantage is that the AS and MS materials are made of screw caps once there is a gap will be obvious cracks, and this material is not impact-resistant.

Acrylic material is actually what we often call organic glass, is an early development of important thermoplastics, acrylic material has good transparency, chemical stability, weather resistance, easy to dye, easy processing, beautiful appearance. Acrylic screw cap toughness and impact resistance, in the case of sufficient budget, you can give preference to the screw cap made of acrylic material.

Gaskets for cosmetic glass bottles

When opening a cream product for the first time, we usually find a hard plastic piece at the mouth of the bottle, which we often call a gasket. The main purpose of using gaskets in cosmetic glass bottles is to maintain a vacuum inside the bottle and prevent the cosmetics from being oxidized. The gaskets are classified according to their shape, and the common ones are hand-pull gaskets and cap gaskets. Hand pull gaskets, as the name implies, have a small protrusion on top of the gasket to allow the user to lift the gasket, while cap gaskets do not. Hand gaskets are generally designed as U-shaped discs to maximize air compression inside the bottle, but this requires the gasket to fit the mouth of the glass bottle in order to provide a seal. The cover gasket is generally flat on both sides and is made of PE. If the glass bottle being sealed is regular, the most common cover gasket, PE cover gasket, is generally used; if the bottle is a positioning product, a double compound physical foam gasket is generally used. Generally speaking, the thickness of the gasket of the cap gasket is 2-2.5mm, and there is also the liner gasket, which is the gasket applicable to the inner liner of the glass bottle. The height of the inner liner of the glass bottle maintains a certain gap with the bottom of the glass bottle. The inner liner is designed to isolate certain cosmetics that will react with the material of the glass bottle from the glass bottle. The inner liner gasket should match the inner liner mouth of the glass bottle without caring about the size of the outer bottle mouth of the glass bottle.

In addition to the above gaskets, silicone gaskets and induction gaskets are also common. Silicone gaskets have strong sealing properties and are generally used for glass bottle pump heads, drip pumps and lotion caps that contain oil and volatile products, etc. The cost of silicone gaskets is 1-2 times higher than common gaskets. Induction gaskets are used to seal the mouth of glass bottles, and the role of the above-mentioned hand gaskets and cover gaskets is the same, but some manufacturers will add a piece of induction gaskets to increase the sealing of glass bottles. In addition, our company also provides products such as  lotion pump.