Soft-touch or soft-feel coatings are employed to create a variety of haptic effects on plastic, paper and metal substrates. Haptic effects can impact a consumer’s perceived value of a product, and influence them to buy it over other similar products. In fact, a recent study by California Polytechnic State University showed not only did customers prefer cosmetics packaged in a container with a soft-touch coating versus a traditional coating, they were willing to pay a 5% price premium.1 Thus it is no wonder interest in soft-touch coatings has increased in recent years. While the study by California Polytechnic State University focused on cosmetic packaging, soft-touch coatings span a variety of markets including automotive interiors, small electronics and appliances.
With the broad range of markets comes the need for a broad range of feel types. In general, a feel type is described in terms of things known to be soft: rubber, velvet, peach skin, rose petals, silk, leather, suede, etc. Not only are these terms highly subjective, the perceived feel varies from person to person. A coating that one observer might describe as velvety, another may find silky. Studies have shown that factors such as age2 and sex3 affect how feel is perceived. In a previous lab study we chose observers of varying age, sex and training to evaluate a series of developmental soft-touch coatings.4 Although most could recognize a soft coating, their perceptions of which was the most pleasing varied widely. While we found that atomic force microscopy (AFM) measurements could be used to distinguish between feel types of coatings with different chemistries,4 additional testing showed that as the chemistry became more similar, the relationship between the AFM adhesion force and feel no longer held. In addition, AFM cannot distinguish the quality of the feel. Thus, for our subsequent studies we used trained observers who could distinguish both feel type and quality to judge the coatings’ haptic performance.