As a developer and manufacturer of water-borne polyurethane raw materials, formulators often look to us for guidance on standards and methods in producing their finished products. This need for guidance has become even more urgent with the introduction of the newer generations of polyurethane dispersions capable of meeting the demands of soft feel plastics. The following is presented as a very basic discussion of the typical steps in the process of using polyurethane dispersions as raw materials in the formulation of soft feel coatings.
The Evolution of Soft Feel Materials
The development and improvement in soft feel plastics such as PVCs and thermoplastic polyolefins (TPOs) continue unabated. Consumers in industries including furniture and automotive interiors have accepted and often demand their rich appearance and tactile superiority as compared to previous plastic materials. The ability to mimic the look and feel of natural materials and fabrics with more cost efficient and durable plastics is now a customer expectation for many product categories. Soft feel polyurethane dispersions (PUDs) have demonstrated their value in producing the touch and appearance characteristics consumers demand.
Related article: Soft feel Formulations: Four Levers to Pull
Considerations When Choosing a PUD
Careful selection of the proper aliphatic polyurethane dispersion is essential to creating a coating that will perform at a high level. The characteristics of abrasion, adhesion and chemical resistance are inherent in starting with the proper resin. Soft feel coatings produced from aliphatic polyurethane dispersions are formulated to create surface appeal on PVC and TPO substrates providing a lasting, rich appearance in end use applications. The application of soft feel coatings onto PVC or TPO substrates can form a surface with a rubbery to suede touch while protecting the durability associated with the plastic substrates.
8 Basic Steps When Formulating with PUDs
Formulating Steps – (1 kg sample)
1.Resin selection is critical to creating a coating with tactile soft characteristics and high durability for automotive, marine, and furniture end use applications. The process begins with a PUD resin containing good elongation, chemical resistance and acceptance of dulling ingredients.
2. Premix additive -Begin the process by mixing a suspension agent and water together and set aside3. Mix Vessel - Add the waterbase aliphatic polyurethane resin to the vessel, start the mixer, and slowly add the Premix additive while mixing the resin for 10 minutes
4. Water Dilution - Add water and mix for 10 minutes
5. Foam and Dispersant Control – Slow the mixer down and add defoamer and dispersant and mix for 15 minutes at a slow speed
6. Water Dilution – Increase the speed of the mixer and add water
7. Add Inorganic material to create Low Gloss - There will be multiple additions of powder while mixing into the vortex of the coating. The additions should be done with the attention of absorbing the material into the coating.
8.Water Dilution and Final Mix - Add more water and set mixer for 30 minutes at low speed.
The coating is now ready for quality testing for both wet and dry properties. Our next blog will describe the laboratory testing and techniques to characterize a soft feel coating. Chase offers an aliphatic resin and formulating assistance to develop a soft feel coating.
Chase Corporation, Westwood, Ma. Founded in 1946 is a leading manufacturer of industrial products for high-reliability applications with a global customer base operating in diverse market sectors. Chase specializes in the manufacture of waterborne polyurethane dispersions supplied to formulators for industrial, consumer coatings, and adhesives providing waterborne solutions. Our outstanding manufacturing and technical support groups can provide your organization with a reliable global supply, unmatched quality, and superior technical support.
Please contact us today to discuss your application.