1、 Composition of production line
The PVB film production line mainly consists of the following core equipment:

Extrusion System
Choose between single screw or twin-screw extruders based on the characteristics of the raw materials. Twin screw extruders are more suitable for high viscosity PVB resins due to their uniform mixing and good plasticizing effect.
Key parameters: screw diameter, aspect ratio, speed range, etc. directly affect production and film quality.
Casting molding system
The molten material is uniformly extruded through a T-shaped die to form a thin film. The design of the mold head needs to ensure thickness uniformity (usually controlled within ± 0.02mm).
The cooling methods are divided into dry (air cooling) and wet (water tank cooling) methods. Wet cooling has higher efficiency, but requires an additional drying step.
Traction winding system
The high-precision traction roller ensures stable width and thickness of the adhesive film, and the winding tension control avoids wrinkles or stretching deformation.
The winding speed can reach 30-100m/min, depending on the equipment specifications.
Auxiliary system
Including automatic thickness gauges, online defect detection, electrostatic elimination devices, etc., to improve product yield.
The waste edge recycling device can reduce the loss of raw materials.
2、 Process flow
Raw material pretreatment
PVB resin is mixed with plasticizers (such as DOP, DBP) in proportion and pre plasticized using a high mixing machine or internal mixer.
The raw materials need to be dried to a moisture content of ≤ 0.1% to avoid the formation of bubbles during processing.
Extrusion
The mixture is added to the extruder, melted and plasticized at 160-200 ℃, and extruded into a film through the die.
Key control points: melt temperature, extrusion pressure, die gap.
cooling pitching
Dry method: The film is gradually cooled by multiple sets of cooling rollers, and the temperature gradient on the roller surface is controlled (such as 80 ℃ → 60 ℃ → 40 ℃).
Wet method: The film enters the water tank for cooling, and the water temperature is usually 15-25 ℃. A water removal device is required.
Post processing
Surface corona treatment enhances the adhesion between the adhesive film and glass (with a Dyne value ≥ 38mN/m).
Cutting, winding, and packaging.
3、 Technical features
high precision control
Thickness uniformity: achieved through fine adjustment of the die lip and online thickness measurement feedback system.
Width stability: The traction roller is driven by a servo motor, with a synchronization accuracy of ± 0.1%.
Energy saving design
The extruder adopts an efficient screw design to reduce energy consumption (unit output energy consumption ≤ 0.3kW · h/kg).
Optimization of cooling system to reduce water resource consumption.
Automation and Intelligence
The PLC control system integrates functions such as process parameter monitoring, fault alarm, and production data recording.
MES system can be optionally selected to achieve full process traceability of production.
4、 Market application
Construction field
Used as an intermediate film for laminated glass to enhance safety performance (impact resistance, bulletproof) and sound insulation.
Typical product: 0.38-1.52mm thick adhesive film, with a light transmittance of ≥ 85%.
Automotive field
The laminated film of car windshield needs to meet the high and low temperature cycling test (-40 ℃ to 90 ℃).
Special requirements: low haze (≤ 1%), anti UV aging.
Photovoltaic field
Used for solar cell packaging, replacing traditional EVA film, improving weather resistance and service life.
Key performance: high transmittance (≥ 90%), low water vapor transmittance (≤ 1g/m ² · day).
5、 Industry Development Trends
Large scale and high efficiency
The width of the production line is expanding to over 3600mm, and the single machine production capacity is increasing to over 1000kg/h.
Functionalization and Customization
Develop special adhesive films such as high barrier, anti fog, and self-healing to meet the needs of segmented markets.
green manufacturing
Using bio based plasticizers and recyclable materials to reduce environmental impact.