Depending on the coating material used, the type of coating is also different. PVDC coating, PVOH coating, silicon oxide (Si0x) coating, Acrylic (Acrylic) coating these four kinds of plastic coating characteristics and applications are introduced.

According to the different coating materials used, plastic coating mainly has the following types:

01/PVDC coating

PVDC emulsions can be coated in several ways, depending on the characteristics of the substrate and equipment conditions.In cases where precise measurement is not required, reverse roll coating is often used.In cases where more accurate coating amounts are required, air knife coating or wire winding bar coating should be used. The former has no physical contact with the substrate during the coating process and can be used at high speeds. The latter is easier to operate, but only suitable for lower speeds.

According to coating online understanding, PVDC coating is generally in the range of 1.5~3.0g/㎡. A coating volume lower than the above recommended value may reduce the barrier, while a coating volume higher than the above recommended value does not necessarily improve the barrier. Can be coated on one side, can also be coated on both sides, the base material can use bidirectional stretching polypropylene film, bidirectional stretching polyester film, aluminum foil, paper, etc. A variety of different barrier films are made according to the choice of use.

PVDC emulsions can be used to coat paper, cellophane, PP, PET, PE and nylon for packaging applications including fast food, cheese, meat and pharmaceuticals.

PVDC coatings have excellent barrier properties and very low oxygen, odor and moisture transmittance. PVDC coating also has good heat sealing, oil resistance, solvent resistance, wear resistance, softness, gloss and flame retardant. However, the PVDC coating layer also has disadvantages, its composite material is not stable enough at low temperatures, and its substrate and finished product should be kept in a room temperature environment with a relative humidity of about 50%.

02/PVOH coating

PVOH is a type of polyvinyl alcohol coated on the packaging film, which provides special oxygen barrier properties for packaging. It's very foggy. It's not yellow. It has excellent optical properties. The reverse concave roll coating method is adopted. Before PVOH coating, it is necessary to apply the primer for optimal coating strength.

The PVOH coating should be included in the middle of the composite layer to protect the coating from moisture, as once damp, the oxygen barrier of PVOH will be reduced.

03/ Silicon oxide (si0x) coating

The silica/silica coating on the packaging material can obtain a similar barrier property to aluminum foil. It is often referred to as a "glass" coating because silicon is the main ingredient in the manufacture of glass containers. The silicon coated film has excellent barrier property and good brightness. These coatings are intended to replace aluminum foil composites, especially where transparency is required for packaging. The silicon oxide coating still has excellent folding resistance and constant barrier property under high temperature conditions, and the evaporative coating method is generally used, and the coating and the substrate surface are mechanically combined.

04/ Acrylic coating

Acrylic coating is used for plastic film to obtain better heat sealing, mechanical properties of packaging, odor barrier, aesthetics and stability. The coating film has low fog, high gloss and flash effect.

Acrylic coatings can be applied on one or both sides of the substrate. Can be waterborne or solvent coated. Coating online to learn that the general use of reverse concave roll coating, in acrylic coating, often need to be undercoated first, in order to obtain the best coating strength

03/ Silicon oxide (si0x) coating

The silica/silica coating on the packaging material can obtain a similar barrier property to aluminum foil. It is often referred to as a "glass" coating because silicon is the main ingredient in the manufacture of glass containers. The silicon coated film has excellent barrier property and good brightness. These coatings are intended to replace aluminum foil composites, especially where transparency is required for packaging. The silicon oxide coating still has excellent folding resistance and constant barrier property under high temperature conditions, and the evaporative coating method is generally used, and the coating and the substrate surface are mechanically combined.

04/ Acrylic coating

Acrylic coating is used for plastic film to obtain better heat sealing, mechanical properties of packaging, odor barrier, aesthetics and stability. The coating film has low fog, high gloss and flash effect.

Acrylic coatings can be applied on one or both sides of the substrate. Can be waterborne or solvent coated. Coating online to learn that the general use of reverse concave roll coating, in acrylic coating, often need to be undercoated first, in order to obtain the best coating strength