What is Dip Molding

Dip Molding Process Details

KEP has mastered the following five steps of the dip molding process to ensure proper formation, vulcanization, and finishing of high-quality dip molded rubber products. 

1. Coagulant Dipping

Depending on design and application, some dip molded rubber products are left to dry naturally. However, unless the wall of the product is quite thin, natural drying can take a very long time. One way to accelerate the dip molding process is to first dip the mold into a coagulant. This speeds up coagulation and, depending on the coagulant, can also facilitate a smooth, uniform finish on the final product. Coagulant dipping can be done inexpensively, making it a cost effective way to achieve greater efficiency during the dip process.

2. (Natural or Synthetic) Rubber Dipping

Rubber dipping refers to the stage in the dip molding process when the mold is dipped into liquid rubber. The thickness of the rubber wall that develops on the mold is determined by how long the mold remains in the liquid rubber tank, as well as any coagulants used earlier in the dip process. The mold can be dipped multiple times in order to achieve a certain appearance, embed structural components, and more.

3. Leach Dipping

The next stage in the dip molding process is leach dipping. The mold is dipped directly into a water bath, which serves to remove unwanted chemicals from the final product, such as proteins, salt, surfactants, and others. Manufacturers must be mindful of water quality, temperature, and flow rate, as well as time spent in the water bath, to ensure an effective leach dip process.

4. Cure or Vulcanization 

Vulcanization, also called curing, is a vital step for any rubber product. In the cure stage of the dip molding process, the product is placed in a highly controlled oven. The heat activates the accelerators inside the rubber material, which triggers the curing or vulcanization process. The vulcanization process transforms rubber from a soft or liquid material to something solid, durable, and flexible. This process is very loosely analogous to culinary baking, which transforms a soft, malleable dough into a finished food item, such as a loaf of bread. 

5. Finish

The final stage of the dip molding process is finishing. There are numerous finishing methods and materials to choose from, including powder, urethane coating, silicone rinse, chlorination, or soap wash. The most common goals of finishing are to achieve a certain appearance, make the final product easier to work with, and prevent the product from sticking to itself or other products. After finishing, the dip process may be considered complete.

More detail about the stages of the dip molding process can be found here > 

Materials & Applications

KEP offers a specialty line of compounds for our customers to choose from when manufacturing dip molded parts, including natural rubber latex, neoprene, and synthetic polyisoprene. Each material offers unique benefits.

Natural Rubber Latex Dip Molding

Natural rubber latex dip molding offers the best elasticity and barrier protection for the lowest cost. Although KEP’s natural rubber latex proteins do not have detectable levels of proteins, there is a nonzero risk of an allergic reaction. Because of this, natural rubber latex dip molding is ideal for applications where latex allergies are of little or no concern. Natural rubber latex dip molding is a popular choice for products such as radiation attenuation gloves, radiopaque Penrose drains, urine bags, finger cots, catheter balloons, ultrasound probe covers, and other device covers. 

Neoprene Molding

Neoprene compounds offer excellent durability in harsh conditions and are free of latex proteins, making neoprene molding an excellent option for situations where latex allergies and sensitivities must be considered. Neoprene rubber is highly resistant to flame, weather, ozone cracking, abrasion, alkalis, and acids, and moderately resistant to oils. The neoprene molding process also results in products that are extremely physically tough and can withstand significant bending and twisting without sustaining damage. Neoprene molding is often used to make products such as surgical bellows, catheter balloons, ultrasound probe covers, and other types of device covers. Protective covers for sensitive electronic devices may also be made from neoprene molding.

Synthetic Polyisoprene Dip Molding

The look, feel, and elasticity of synthetic polyisoprene is comparable to natural rubber latex, but without the potential for Type 1 latex allergic reactions, making synthetic polyisoprene dip molded products a safe replacement for hard rubber. Synthetic polyisoprene dip molding is often used to make finger cots, catheter balloons, ultrasound probe covers, and other device covers.

Benefits of Dip Molding

Whether you need products for a brand-new startup or a large multinational corporation, choosing dip molding for your manufacturing process can offer you several benefits. KEP ensures high quality and consistency for our dip molded rubber parts, manufacturing products that a wide range of industries rely on and trust. The dip molding process is cost-effective and ideal for rapidly manufacturing products at any scale you need, large or small.

Custom Dip & Prototypes

KEP runs a custom batch dipping operation, giving us the capabilities and expertise to produce small batches of highly customized, niche products and prototypes to our customers’ exact specifications. Our dip molding process expertise includes both automated continuous dipping and semi-automated batch dipping processes, and every step is overseen by dip process experts with years of hands-on experience. We can also scale up production to produce greater quantities of dip molded rubber products, while still offering extensive customization options.

KEP Dip Molding

At KEP, we have over 60 years manufacturing top-quality dip molded rubber products. We use our ISO 13485:2016 quality management system to ensure total quality for all our products. Our raw materials, production machinery, and gauges are all strictly tested, monitored, calibrated, and maintained at every step of the dip molding process. 

KEP is based entirely in northeast Ohio, with our natural rubber latex dipping operation just outside Akron, the city known as the Rubber Capital of the World. We also offer neoprene molding, synthetic polyisoprene molding, and a wide variety of other rubber and elastomer manufacturing services. We are the only domestic manufacturer of natural rubber latex tubing and one of very few dip molding companies that houses its entire dip molding operation entirely on American soil.

Have specific questions about our dip molding process, or ready to get started on your dip molded part or product? Our experts are happy to help – Reach out to KEP today!