Coagulation Line, 1800mm Working Width, 1997, 350m Coagulation Length

Description

  1. Overview
    1. Coagulation line
    2. Year 1997
    3. Not worked much; full documentation available (user manuals, electrical/electronic/mechanical books, layout)
    4. Working width: 1800 mm
    5. Coagulation length: 350 meters
    6. Production process of coagulated products/fabrics - general
    7. Precipitation of polyurethane from solution, creation of a microporous coating structure, providing the material with appropriate properties (breathability, softness, durability)
  2. Materials And Raw Materials
    1. Pu solution in solvent (usually DMF - dimethylformamide)
    2. Substrate (fabric, knitwear, canvas)
    3. Coagulation medium: water or water/DMF mixture
    4. Additives: pigments, blowing agents, stabilizers
  3. Line Equipment
    1. Coating line (knife over roll / reverse roll)
    2. Fabric unwinding station
    3. Coagulation bath (water solution + DMF 15-22%)
    4. Foulards (water washers)
    5. Solvent rinsing and recovery system
    6. Pre-drying
    7. Needle frame
    8. Drying chambers
    9. Temperature control system
    10. Left-hand grinder
    11. Transport rollers
    12. Ready product collection station
  4. Process Flow
    1. Coating application
    2. Apply the PU solution evenly to the weaved fabric (PES/cot – like impregnation)
    3. Pre-coagulation in the bath
    4. Drying on hot rollers
    5. Application of the PU solution by the knife (roller or coating knife)
    6. Coagulation in the main coagulation bath
    7. Monitor: layer thickness, solution viscosity, line speed
    8. Main coagulation: introduce the coated material into the coagulation bath (water or water/DMF)
    9. The following exchanges occur: solvent (DMF) diffuses into the bath, water diffuses into the PU layer → polymer precipitation
    10. Critical parameters: bath temperature: 20 to 60°C
    11. DMF concentration in the bath: 0 to 30%
    12. Residence time: 1 to 10 min
    13. Mixing intensity
    14. Structure formation: porosity control through: temperature, bath composition, mass/PU content
    15. Transfer rate
    16. Rinsing: removal of residual DMF from the material several stages of water baths (cascade)
    17. Drying: oven drying: temperature: 80–140°C, shrinkage and stress control
    18. Left-side sanding (prevents product sticking in the roll and opens micropores)
  5. Control Parameters
    1. Coating thickness
    2. Porosity/vapor permeability
    3. Mechanical strength
    4. Adhesion to the substrate
    5. Residual DMF content
  6. Hall Dimensions
    1. Main hall: 84200 mm x 10900 mm x height 8500 mm
    2. Paste hall: 18600 mm x 12100 mm x height 8500 mm