EpoxyEpoxy resins form the base of several GTS adhesives. More
- These are generally modified to give suitable flexibility and bond strength to plastic films.
- Epoxy has good resistance to heat, chemicals and humidity after curing.
- The adhesives may be soldered and are compatible with all main FPC film types.
- Addition of fillers is also easy, so flame-retardants and colours may be added.
- Systems with improved thermally conductivity are also available.
- The main advantages of epoxy systems are that they are compatible with standard rigid-board (PCB) processing.
- GTS Standard Product series: Laminates: 5670 / 7800 / 7870, Tapes: 3840 / 3870
AcrylicAcrylic systems have historically been used with PI films and have a long history especially in the U.S. marketplace. More
- Acrylic systems are used mainly with PI films and may be specified in drawings, being one of the older adhesive types.
- They have good solderability when cured and retain flexibility.
- Chemical resistance is also good.
- Acrylic resins are recommended when bonding to alternative metals, such as stainless steel or nickel alloy as the bond strength remains high, and can tolerate some rolling fluids.
- Temperature resistance is generally lower than epoxies.
- Processing of plated through holes may require a plasma de-smear technique due to softness and chemical resistance of acrylics.
- GTS Standard Product Series: Laminates: 7700, Tape: 3770
Polyester / PolyurethaneThis is the oldest type of adhesive used for FPC and flexible composites, dating back to the early 60’s. It is particularly useful for bonding of PET film as it retains good bonding to more difficult substrates. More
- PU is characterised by being softer and more flexible than other standard adhesives.
- PU adhesives are highly adaptable and can be modified to improve chemical and temperature resistance, or to add fillers or colours.
- Some types are solderable with PI film.
- Main disadvantage is that of hydrolysis - they are susceptible to humidity attack.
- GTS standard product series: Laminates: 5500 / 5560 / 5570 / 5660 / 7600, Tapes: 3000 / 3010 / 3020 / 3200 / 3300 / 3400 / 3410
HT SystemsGTS manufactures a range of high-temperature (HT) systems for higher operating temperatures, up to 150 C. More
- Typically epoxy, acrylic and PU systems are suitable up to a continuous use temperature of 120C, but there are many applications that require higher than this, for example automotive engine compartment circuits.
- The main target for GTS is to retain flexibility for these systems and this is done by compounding resins and use of polymers with inherent temperature resistance.
- Contact GTS for information on adhesives and products.