After a short introduction of printable pressure sensitive adhesives (PSA), the presentation will focus on UV PSA applications, the manufacturing process, new adhesion performance test data and characteristics of the adhesive if it is over- or under-cured.  The session also will highlight bonding to new surfaces such as digital inks, with test data presented.  The presentation will conclude with a discussion on new applications for printable PSAs as the products evolve.

Printable UV PSAs do not require space-consuming ovens, eliminate screen clogging due to evaporation and produce a more consistent adhesive thickness compared with solvent and water-based printables.  New UV PSAs have improved adhesion performance and more robust cure windows compared with past UV products.

Traditionally, resistors are used in electronics as current limiting devices and voltage dividers. However, there are many other uses such as heaters, temperature sensor and force sensors. While there are several options to achieve a desired resistance value and/or functionality (thin film, plated resistor technology), screen printed-polymer resistors are a cost-effective and reliable method for creating resistors for many applications.

The control of resistance value in printed resistors can be accomplished by using materials with different bulk resistivity together with the length and cross-sectional area of the printed resistor.  Since the value of a resistor of a known bulk resistivity is directly proportional to the aspect ratio of the resistor’s length, width and thickness, the resolution and uniformity of thickness in the printed resistor is critical in achieving the desire values.  The session will provide theoretical and practical recommendations for optimizing screen printer setup to achieve the desired resistor value, and minimizing variation.

EL lighting has proven to be attractive and appealing for membrane switch applications. The diffuse light source is both easy on the eyes and helpful in locating switches and user communication. This presentation will explore the selection of the right brightness level for switch application, effects of ink formulation on phosphor life, and a proposed new metric for changes in brightness.

It will also explore some electronic solutions for brightness longevity. Brightness level for a switch should be based on the environment and need. For dark areas, it is important the brightness not be too high because it can be uncomfortable or distracting to view. Current standards and practices will be reviewed and considered.

Phosphor life is affected by electrical field conditions and environmental protection. Ink formulation also can have a significant impact on both of these factors. Data will show the major effects in these areas. Two new metrics have been proposed for tracking phosphor longevity. The first is similar to those used today, at a percent change of 1,000 hours. This is similar to industrial data that gives changes for 24 hours and 100 hours. This is a compromise between useful data and the length of time required to collect data. The second metric is the voltage change required to maintain 75 percent brightness. This metric is useful for understanding applications in which constant brightness is desirable.

The speaker will present a basic overview of how these measurement instruments work and how they are used on membrane switches, overlays and EL lamps. Instruments used on the various components, such as those in overlays and membrane switches, are used to quantify the brightness and chromaticity requirements of the light sources used in these applications.

The presentation will show how choosing the correct instrument is important in characterizing the light sources, overlays and filters used in industries, such as aerospace, automotive, and on appliances. It is important to quantify each component in the design stage, manufacturing and final QC with the proper instruments. The speaker will explain how the data obtained from the instruments is used.