Summary Of Processing Methods For Laminating Film

- Nov 02, 2017 -

Composite membrane can improve the characteristics of a single film, can improve the protection of the contents, including moisture, oil, barrier, shading and air tightness. According to different substrates and different uses, laminating film processing methods can be divided into the following five categories:

Dry compound method

The method is a method in which a binder is applied to a surface of a substrate by a laminating machine, and the heating roller is pressed against the other film. This method is almost applicable to all substrates, how many layers can be compounded, has been widely popular in all areas of packaging materials. The cost of the equipment is cheaper than the extrusion machine. Recently, due to the retort treatment and boiling sterilization of the packaging function requirements more stringent, the adhesive and more use of excellent adhesion of the polyurethane series. In addition, the residual solvent in the dry compound method leads to dangerous problems such as pollution, fire and explosion. In order to solve these problems, it has developed a composite system with different organic solvents - solventless compound method, which has the following advantages:

· No solvent to reduce environmental pollution.

No risk of fire and explosion.

• No solvent drying required to save energy and equipment footprint.

• No solvent on the printing ink.

· Do not need to recycle solvent plant investment.

· Cost reduction due to increased production speed.

2. Wet compound method

The method is mainly used for aluminum foil and paper, thin paper, ordinary cellophane and other porous materials on the composite. Water-soluble adhesives (gelatin, starch), water-dispersible adhesives (vinyl acetate latex, etc.) are coated on the surface of the substrate in a wet state and compounded with other materials, followed by roll adhesion and drying. This method is simple to operate, and with a small amount of adhesive can be compound, the thickness of the thin aluminum foil (5 ~ 6μ) can be compounded, compared with other composite methods, fast and can be a lot of processing, processing costs are very low , Without organic solvents, good security, no residual solvent to paper-based materials as the center of the market is relatively stable.

3. Extrusion method

This is the most commonly used method for compound processing. The PP, PE, EVA (ethylene-vinyl acetate copolymer) ion resin and the like are extruded into a film by an extruder, and are coated with a process agent (polyethyleneimine, Polyurethane-based resin, etc.) on a variety of films to be compounded, and then by cooling, curing. The method saves labor, due to the use of adhesive resin (maleic anhydride modified olefin resin, maleic anhydride and other block modified olefin resin, etc.). Therefore, the use of adhesives, can reduce the process to achieve the purpose of reducing costs.

4. Hot melt compound method

The method comprises the following steps: blending rosin, xylene resin, styrene resin and the like in a substrate resin such as hot melt EVA (ethylene-vinyl acetate copolymer), EEA (ethylene-ethyl acrylate copolymer), PE, butyl rubber and the like Adhesives and paraffin-like adhesives are coated on the surface of the film, the surface of the aluminum foil, and the mixture is cooled on the other substrate immediately.

It is mainly used for the production of various containers of the lid, and requires a resistance to cooking, in the EVA and other substrate resin mixed with adhesive, the substrate for extrusion coating can improve heat resistance.


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