I. Factors affecting the performance of vapour plated silicon oxide barrier packaging films

Vapour plating base film, vapour plating method, vapour plating conditions as well as the composition of the vapour plating coating and the thickness of the vapour plating layer may have a great impact on the performance of vapour plated silicon oxide barrier packaging films, which can be mainly listed as follows. www.susumino.com南京住野精工阻隔膜生产线

1. Selectivity of the substrate
As mentioned earlier, the barrier properties of vapour deposited silicone oxide barrier packaging films are dependent on the SiOx coating and therefore the coating cannot be damaged during the vapour cooking process. Steamed silicone oxide barrier packaging films are often laminated with other films to create steamed films and the selection of the steaming substrate should take into account the following issues.

(1) Type of plastic film

The adhesion fastness between the vapour-plated silicon oxide film and the plastic film has a greater relationship with the type of plastic base film. PET, PVC and other polar films have better adhesion with silicon oxide, while non-polar films, with silicon oxide, have poorer adhesion.

(2) Surface state of plastic films

The barrier properties of vapour plated silicon oxide barrier packaging films are influenced by the thickness of the vapour plated layer, but to a greater extent by the uniformity of the silicon oxide coating. In addition to the chemical composition and structure of the vapour plated layer itself, the smoothness of the surface of the base film used is also an important factor in the formation of defects, the greater the roughness, the easier it is to cause vapour plating defects, but the right amount of roughness will enable the formation of a physical anchor between the vapour plated layer and the surface of the base film, improving the interlayer adhesion.

(3) Surface pre-treatment condition of plastic films

In order to obtain good quality vapour deposited films, a moderate surface corona treatment of the base film is necessary. After surface corona treatment, an oxide layer can be formed on the surface of the plastic film (through a variety of complex chemical reactions such as cross-linking, ozonation, carboxylation and nitroxylation, atoms and atomic groups such as oxygen and nitrogen are introduced to the surface of the plastic film), increasing the bonding force between the base film and the vapour deposited coating. In the case of certain pretreatment equipment, if the pretreatment time is insufficient and the surface modification is not adequate, it will lead to a decrease in the bonding fastness between the base film and the coating; too long a pretreatment time may cause a weakening of the interface of the base film at a deeper level, producing a weak interface layer of the base film itself, which will also cause a decrease in the bonding between the surface of the base material and the vapour plating layer.
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2. The effect of vapour deposition process conditions on the performance of vapour plated silicon oxide barrier packaging films

Regardless of whether physical or chemical vapour deposition is used, the vapour deposition process conditions may have a significant impact on the performance of vapour deposited silicone oxide barrier packaging films, so process conditions that are conducive to improving the barrier properties of vapour deposited films should be used wherever possible.


(1) When physical vapour deposition is used, the

The level of vacuum, the temperature of the substrate film, the power of the electron gun, the shape of the raw material to be vapourised, the speed of oxygen introduction in the vacuum chamber, the thickness of the vapourised coating (determined by the vapourisation time and evaporation power) all affect the performance of the final product.

The higher the vacuum level during evaporation, the better the evaporation of SiO2 and the higher the quality of the evaporation coating produced.

②The higher the temperature of the plastic base film during evaporation, the better it is for the evaporated SiO to be deposited on the plastic base film, forming a dense coating and improving the adhesion between the evaporation layer and the plastic base film, so raising the temperature of the plastic base film appropriately is conducive to improving the quality of the evaporation film.

③The use of electron gun bombardment, evaporation of SiO2, it is appropriate to use the block of SiO2, because the powdered SiO2 in the electron gun bombardment, easy to produce powder sputtering phenomenon, affecting the quality of evaporation coating, and powdered SiO2 is conducive to resistance heating evaporation.

The greater the amount of oxygen, i.e. the greater the value of x, the more the vapour layer moves in the direction of increased transparency, but the barrier has a tendency to decrease. When x is equal to 2, a colourless and transparent evaporation layer with poor barrier properties is obtained. x is usually controlled between 1.5 and 1.8 to obtain an evaporated silicon oxide film with both high barrier properties and good transparency. www.susumino.com



When the thickness of the vapour layer increases, the barrier of the vapour coating increases, but when the thickness of the vapour layer exceeds 50nm, the barrier of the vapour coating remains basically unchanged if the thickness of the vapour layer is further increased, so it cannot be expected to improve the barrier of the vapour coating film indefinitely by reducing the line speed of the production line (increasing the vapour coating time) and increasing the thickness of the vapour layer.


(2) chemical vapour deposition, high-frequency electromagnetic wave or microwave frequency selection, should be ionised with the ionisation energy in the atmosphere and the energy required for the ionisation of the vapourised material to match, high-frequency electromagnetic wave is generally selected 13.56MHz, microwave is generally selected 2.45MHz, vacuum in about 10-2Pa can obtain excellent vapour deposition effect, while physical vapour deposition requires a higher vacuum, namely 10-2~10-3Pa or higher.

Nanjing Sumino Precision Machinery Co., Ltd. is a high-tech enterprise integrating scientific research, production and sales, and has always adhered to the business philosophy of honesty, equality and customer interest first. In order to better improve the quality of our equipment and step into a more professional and standardised production track. We have set up independent research and development technology centres and production departments for seven major types of equipment, including plastic sheet and plate, cast, bi-directional stretch, non-woven non-woven meltblown fabric, laminated film, recycled pelletizing and environmental recycling systems and coating machine manufacturing systems. We offer a full range of technical solutions to meet the specific needs of each customer. The following lines are available for customisation: PE double/three layer co-extrusion lamination line, LDPE (3 in 1) lamination line, PP, PE, PLA double sided lamination line, aluminium foil high speed lamination line, PP spunbond lamination line, textile lining lamination line, hot melt spray lamination line, multi-layer extrusion laminating line, graphene coating laminating line, carbon fibre laminating line.