Polymer Layering
The application of a formulated polyvinyl chloride resin onto a fabric substrate to create a durable waterproof barrier defines a major finishing method for heavy-duty industrial textiles. This finish, known as a pvc coating, provides excellent resistance to abrasion, chemicals and weather. It is commonly applied to fabrics used for tarpaulins, protective rainwear and luggage.
This layer of polymer effectively seals the weave, making the composite fabric completely impermeable to both liquids and gases under standard operating conditions.
Application Process
Liquid resin is applied to the base fabric using a knife-over-roll or transfer coating system. During the process, the pvc coating must be cured in a drying oven at high temperatures to fuse the resin particles into a continuous polymer layer. This thermal processing is critical to ensure that the plastic layer adheres strongly to the underlying fabric.
Restricted Additives
Formulations often contain phthalate plasticizers to maintain flexibility in cold temperatures. Because of these additives, brands monitor the pvc coating through routine laboratory testing to ensure it complies with restricted substance lists. This testing protects children and adult consumers from exposure to regulated chemical compounds.
Mechanical Testing
Adhesion and tear strength of the coated fabric are evaluated at shipment checkpoints to ensure structural performance. A poorly applied pvc coating will peel away from the base fabric under stress, leading to premature failure of the product in the field. This laboratory evaluation is necessary for certifying that the cargo meets the customer’s durability specifications.
