Low temperature curing, high reliability, conductive adhesive TK PASTE CR-5200

Low temperature curing, high reliability, conductive adhesive TK PASTE CR-5200

The evolution of mobile and wearable devices has led to an increase in components made of light and thin resins and films. Because these components are vulnerable to heat, solder cannot be used in an increasing number of cases. KAKEN TECH's TK PASTE CR-5200 is a low-temperature curing one-component epoxy resin type developed for conductive bonding of parts and circuits with low heat resistance. It is a conductive adhesive with low resistance and excellent reliability that uses specially shaped TK silver powder, and has already been used in many mobile products.

General characteristics

Merit	Low temp. curing, low resistivity
Binder	Epoxy resin
Curing condition	100℃×60min
Specific resistivity	3×10-4Ω・cm
Viscosity(@25℃ 5rpm)	30Pa・S
Pot life(@25℃)	25hrs
Storage condition	below-10℃
Container	10g/5cc syringe

Recommended Applications

	■ Camera modules ■ Wearable devices such as wireless earphones ■ Internal electrodes for sensors ■ Component mounting on film devices

Feature 1: Low contact resistance

Unlike solder, conductive adhesives have contact resistance at the interface of the connection. Even if the specific resistance (resistance of the adhesive itself) is low, if the contact resistance is high, the resistance of the entire circuit will increase. TK PASTE CR-5200 has extremely good conductive performance because the contact resistance is greatly reduced by the effect of specially shaped TK silver powder.

Contact resistance to SUS 316L

What is contact resistance?

Resistance present at the interface between the adhesive and the component. The above graph is the result of bonding a SUS316L plate with each conductive adhesive as shown in the photo on the right and measuring the resistance. Stainless steel in particular has a passive film on its surface, which deteriorates contact resistance, but CR-5200 has good conductivity.

Feature 2: Superior Reliability

When dissimilar metals come into contact with each other in a humid environment, metal corrosion occurs due to the transfer of electrons (known as potentiometric corrosion or galvanic corrosion).	Corrosion due to contact with dissimilar metals (galvanic corrosion)
Conductive adhesives contain silver (Ag), and depending on the material to be bonded, conductivity and strength may deteriorate due to metal corrosion when subjected to high temperature and high humidity tests. In particular, tin (Sn) is commonly used for soldering to terminals of electronic components. However, tin has a large potential difference with silver, making it a combination that is prone to metal corrosion, so it is essential to pay attention to this combination.
TK PASTE CR-5200 prevents the progression of metal corrosion with specially shaped TK silver powder, and maintains good conductivity even in high temperature and high humidity tests over a long period of time.

Comparison of resistance change between CR-5200 and conventional conductive adhesives in high temperature and high humidity test

Sn conductors were fixed on gold (Au) terminals with conductive adhesive, and the resistance was measured for each hour after being put into a high-temperature, high-humidity testing machine.