Silver-filled polyurethane adhesives are starting to appear on the market. They are two-part adhesives, so they either require mixing or they are supplied pre-mixed and frozen like the snap-cure epoxies. They offer high peel strength and flexibility. As they are silver filled, high levels of conductivity can be achieved (around 0.0001 Ohms∙cm to 0.0004 Ohms∙cm). The liquid itself will contain different conductive adhesives such as iron, copper, gold, etc, and will disperse these equally in the form of a polymer resin. The resin can be applied to several different areas of use and will help make repairs for instance. Product Types Electrically Conductive Adhesives (ECAs) are used for high-reliability applications such as aerospace, medical, automotive, and consumer products. However, Henkel also offers ECAs that are non-noble metal compatible which are ideal for handheld consumer devices. In both cases, conductive glues, adhesives, and epoxies offer viable lead-free solder alternatives for active and passive component attachment across a range of applications.

An unfilled epoxy ideal for fast-curing applications: 2 minutes at 150C. Ideal for Smart Card applications. There are many kinds of conductive epoxies, glues, and rubbers available. Unfortunately, they are for the most part quite expensive. ECAs can be used in applications which involve high reliability or temperature sensitive components. With an array of curing temperatures and application methods (jetting, screen printing, dispensing) electrically conductive adhesives offer flexibility to a production line and a wider scope for electronic assembly.

Industrial Applications for Electrically Conductive Adhesives

Henkel’s LOCTITE ® range of conductive adhesives for electronics offer strong component and PCB interconnections for on-demand, long-term, and reliable performance. Our broad portfolio of electrically conductive pastes is formulated using a variety of base chemistries including acrylate, epoxy, and silicone platforms, each of which is designed to provide manufacturers with choice and flexibility for varying requirements.

A B-Staged epoxy also suitable for lid attach. A-stage cured in 10 seconds using UV light, then B-Staged in the oven for 40 minutes at 150°C. Suitable for a flexible manufacturing process. Certain temperature-sensitive electronic components cannot be soldered because the intense heat of liquid solder and the soldering iron can cause damage to the component. This type of application calls for an electrically conductive adhesive that can be used instead of solder. PCBs with components attached to both sides can also benefit from using an electrically conductive adhesive as the assembly process is easier without the risk of components dropping off the underside when parts are soldered on the top. When using electrically conductive adhesive for an entire electrical assembly, it negates the requirement to undergo a solder re-flow process. Soldering is a relatively straightforward process, but it is important to solder safely and ensure the correct equipment and soldering iron tip is used to create a secure join. Safety is essential so always make sure you are fully prepared for the task before using soldering equipment. Copper Tape for Shielding Suitable for fine-pitch flip chip interconnections where electrical conductivity is desired in only one direction This conductive glue is a fraction of the cost of any other conductive glue including "Wire Glue". You can mix it up in large quantities. As you can see, I have barely scratched the surface of what is possible with an inexpensive conductive glue and glued circuits. Perhaps these circuits could be silk-screened on. Maybe one could paint glue on a surface and then use a laser to remove where you don't want it to conduct and etch a circuit that way. Circuits can be constructed on various 2 and 3 dimensional surfaces including paper, cardboard, plastic, fabrics, and glass. As mentioned above, many components such as capacitors, diodes and transistors might also be constructed.There are a number of reasons electrically conductive adhesives might be a more suitable alternative to other methods of bonding and adhesion. These high-performance adhesives are often used as an alternative to solder in applications where the components being bonded are temperature sensitive. Given the cure temperature of an ECA is far below that of relfow temperatures, this opens the door to sensitive componentry, less energy usage, and flexibility of processing

A high viscosity unfilled epoxy with independent heat-curing (60 minutes at 80°C) and light-curing (2 - 6 seconds at 60 mW/cm2) mechanisms. Very high Tg of 185°C. As with many things in life, there are certain trade-offs. In the case of electrically conductive adhesive they are:

Why should we use a conductive epoxy?

Due to its versatile nature, copper foil tape can be used in a wide range of applications and environments. It is used by professionals and hobbyists alike, across a spectrum of uses including electro-magnetic shielding, slug repellent, and DIY crafting. Until recently, the curing of conductive adhesives was a slow process. Thanks to new hardener systems, conductive adhesives can be now cured within a few minutes: Several one-part Elecolit ® conductive adhesives have been modified for snap-curing ability. Production line considerations. Firstly, how fast is the throughput? Secondly, is the process fully automated or manual? How will you dispense the adhesive? A fast-curing epoxy (3 minutes at 150°C) with excellent compliance for larger die applications. Can be light-fixed in seconds for high-placement accuracy. Very long pot life of 7 days. Two-component epoxy adhesives comprise resin and hardener and are available in a range of viscosities. However, if heavily filled with conductive metal, viscosity can become quite high. If filled with silver, volume resistivity can be as low as 0.0001 Ohms∙cm.

Conductive epoxy, also known as electrically conductive adhesive or conductive glue, is a material that consists of an epoxy resin mixed with a conductive filler. These resins require “curing” or a “setting time”, before the connection is secure. This means that the glue hardens out. The conductive material contained in the epoxy is often silver (Ag) or a form of carbon (graphite). An example is Ablebond’s 84-1LMISR4. Why should we use a conductive epoxy?Electrically conductive adhesives are used in SEM to fix and ground the sample to avoid electrostatic charging of the surface. This is the ability of the adhesive to store a charge (electric flux). This is affected by the temperature, and also the glass transition temperature (Tg) of the adhesive as insulating properties change above and below the Tg. So, the higher the Tg, the better the retention of dielectric properties at elevated temperatures. Typical values for insulating epoxy glues are around 4 to 6 at around 1 mHz. Volume Resistivity For over two decades, 8330 has been our flagship product. Now, after much research and development activity, we are excited to announce 8330 will be replaced by an improved version, 8330D. 8330D offers improved productivity, curing at room temperature in only 5 hours instead of the 24, while offering twice the working time, 20 minutes instead of the old 10 minutes. As well, 8330D offers improved conductivity and flowability. It also provides higher safety, being free of SVHC’s and no Proposition 65 listed ingredients Conductive Adhesives are used as an alternative to soldering in some cases and typically found in applications such as;