Dip Coaters Information


Dip CoatersDip coaters operate by immersing a substrate (substance requiring modification) in a liquid before withdrawing it at a measured pace within a controlled environment. Coating thickness is determined by the speed of withdrawal and liquid viscosity.


When coatings are prepared with reactive substances, as with sol-gel coatings, atmospheric conditions are manipulated allowing the solvent to evaporate. As a result, the gelatin process forms a transparent film around an object. The method is employed in the coating of sizable or complex substrates.


The procedure takes up to dozen steps, depending on the task involved. Manufacturing of various items, including plate glass, solar energy devices and tinted windows is achieved using this technique. Another function of dip coating units is applying an optical coating on light bulbs.


The same approach is employed in making thin film products such as latex gloves, toy balloons and urinary catheters in high volumes, at a consistent thickness. Production costs rank favorably against competitive procedures given the output volume achieved through dip coating or molding. Low costs allow for rapid production line changes to accommodate new substances and designs.





While standard dip coating machines exist for condom or glove manufacturing, most equipment is custom built for specific requirements. Two main formats are employed in dip coater design:


Batch production -- Dip coaters of this type incorporate dipping molds, also known as “formers,” mounted on pallets. These mechanisms function by intermittently moving pallets, at a consistent interval, to individual machine stations where they pass over a dipping tank. In some setups, the tank is elevated to the pallet for dipping. Formers are affixed in one place, however, they can be spun around the axis of the pallet. Dip coaters supporting vertical dipping via batch indexing utilize electric motors, compressed air or hydraulics to power their operations.


Continuous chain production -- This approach sees multiple racks of molds or individual formers attached to a conveyer belt. The line moves at a uniform speed, propelling the molds through the coating process. The procedure involves passage through dipping tanks and ovens. Such coaters feature both rotational and fixed forms, depending on operational requirements.





Dip coaters manufacture a multitude of products, including:


  • Medical gloves
  • Swim caps
  • Coated glass
  • Prosthesis covers
  • Balloons
  • Engine head gaskets
  • Artificial heart casing
  • Coated parts
  • Rebreathing bags
  • Breast implant casings
  • Face masks
  • Unsupported work gloves
  • Cast covers
  • Shoe covers
  • Supported work gloves
  • Medical bellows
  • Latex toys
  • Medical tubing
  • Foam drink can insulators
  • Penile implants
  • Medical bags
  • Tool handle grips
  • Nose cannulas
  • Windshield wiper boots
  • Medical Drinking cup caps
  • Blood pressure cups
  • Industrial plugs
  • Coated automotive rods
  • Medical connectors
  • Airways
  • Medical cushions
  • Plated electrical parts
  • Probe covers


Selecting Dip Coaters


Factors related to performance, operating capacity and output requirement need to be considered when choosing a dip coating/molding equipment. These include:


  • Wall thickness, shape and design of the machine
  • Type of polymer involved
  • Dipping life cycle to maturity of the polymer or substrate
  • Anticipated system production output
  • Multiple or single production system


In addition, the following parameters should be investigated:


Dip CoatersProduct variety -- A majority of dipping mechanisms are designed to create a single item. The integration of continuous chain technology reduces costs and enhances productivity while allowing companies to maintain a competitive advantage. Most dedicated single element systems rely on this approach.


On the other hand, systems using the batch dipping method are preferred when dealing with diverse products. Such setups serve the production of specialty items with high-profit margins. Some dip coaters have the capacity to deliver multiple components simultaneously on the same machine.


Process flexibility -- Batch dipping machinery provides more flexibility when it comes to adding new items to a manufacturing line or switching existing processes to improve efficiency. Speed is an important component of the systems’ performance. Any method for increasing the rate of output requires testing on the whole production line before implementation.


Film thickness --  To maintain quality, the coating should result in consistent and uniform wall thickness. As wall thickness increases, batch dipping is utilized for components exceeding 15 mm in thickness. This applies to products such as Foley catheters, baby pacifiers, and electricians’ gloves.


Polymer type -- Modern dip coating employs a more extensive array of polymers compared to the past decades. Latex is no longer the only viable material for use in dip molding activities. Allergy issues associated with latex have led to the development and integration of alternative materials in the making of medical products. Catheters and medical balloons are now made from polyurethane or silicone.


Water-based vs. synthetic solvent based -- Dip coater setups based on solvents cost more than water-based versions. The additional expense stems from the use of explosion resistant motors as well as machine enclosures or robust ventilation to protect system operators.


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Engineer Direct | Nadetech