Plastic coatings are coatings that are created and applied through the plastic manufacturing process of plastic coating, which is also sometimes called immersion coating.
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Advantages of Plastic Coating
Plastic coatings offer manufacturers and end-users many benefits. For example, plastic coating is a very economical and efficient process. Because liquid in the vat that remains unused after a dipping process may be reused, manufacturers experience very little material waste. They also reduce their carbon footprint by minimizing the volume of their fossil fuel-derived material usage. Plastic coating is easy to master and execute. For help determining one’s process choices related to materials, dip, dwell and withdrawal times, an interested party should turn to a knowledgeable plastic coating specialist.
Application of Plastic Coating
Plastic coating materials have many applications, from decoration to protection. Industries that use them include: aerospace, medicine, automotive, electronics, food processing, pharmaceuticals, chemical processing, transportation and construction. Plastic coating applications include: electrical wires, wire hangers, outdoor accessories, hood latches, biological adhesives, feeding tubes, needle roller bearings, soft tissue replacement, textile manufacturing rollers, pill coatings and the improvement of the comfort and grip of machine and appliance handles.
Design of Plastic Coating
Plastic coatings are formed from a molten polymer or plastic for the purpose of providing a protective and/or insulative covering for manufactured parts or components like wire forms, electrical wires, household tool handles, medical equipment, sports equipment and more. Most often, plastic coating is performed via the method of dip molding, which is the most cost-effective and efficient of all plastic coating methods available.
Plastic coatings, also called polymer coatings, are selected based on their respective molecular structures, deposition processes (when thin layers deposit themselves onto the object as it is withdrawn from the vat), correlations with physical functions and properties and applications and testing. For example, careful consideration must be given to the polymer that will insulate electrical wires and components, because they must be able to reduce the risk of shock or fire, as well as keep them from interaction with dirt and moisture and from direct contact with the people handling them. The correct plastic coating must also be selected for items that require improved corrosion resistance, such as wire hangers, outdoor metal hooks and accessories and fencing. Possible plastic coatings include thermoplastics, polyesters, polyamides, phenolics, polyvinyls, polyethylene, acrylics, polystyrene and plastisol.
Process of Plastic Coating
During the process of dip molding, manufacturers employ dip molders. Dip molders create plastic parts, products and coatings by lowering objects, called substrates, into a vat of a molten polymer or plastic, where the plastic surrounds and sticks to the surface of the object. Of the many materials available for use during plastic coating, the most commonly utilized one is plastisol. Plastisol is popular because it needs only to sit at room temperature in order to melt and because, upon being heated, it solidifies permanently. The low melting point of plastisol is an excellent feature because it means plastisol requires the use of less energy to perform dip molding, which saves manufacturers time and money. To ensure complete coverage or to create a specific partial coverage pattern, a primer may be applied to the whole or portions of the surface of certain materials.
After a predetermined period of time, the substrate is lifted slowly and carefully from the molten plastic, and set where it is allowed to harden and cool. The length of time that the substrate is immersed in the plastic, a period called the "dwell time," determines the thickness of the plastic coating, which may be as thin as .25 inches, though it is usually thicker than that. Generally, the longer the dwell time, the thicker the plastic coating layer. Removing a coated substrate from a vat too quickly may cause surface irregularities. This speed, called withdrawal speed, along with dip speed, immersion times and oven temperature, all influence the final quality of the coating.
Types of Plastic Coating
There are two types of plastic dip coating: hot dip coating and cold dip coating. Hot dip coating, which requires a substrate to be heated prior to immersion, is used when a thicker layer is desired. Cold dip coating, on the other hand, is used to make thinner layers of plastic coating. During cold dipping, an unheated substrate is lowered into a liquid polymer, then placed inside a heated chamber, where the fusion completes. Regardless, any object that can fit into a vat and withstand the heat of molten plastic, may receive dip molded plastic coatings. Within hot and cold dip coating, manufacturers have the freedom to customize and adjust material choice, thickness, texture, color and the like, to meet a customer’s specifications.