New generation of Elpemer® solder resists: Directly imageable and high-temperature resistant
“The new green aqueous-alkaline developable ELPEPCB® solder resist Elpemer® AS 2467 SM-DG copes with the increased requirements specified by PCB manufacturers and OEM customers in terms of sustainable solder resists.
Unique worldwide, this combination of direct imaging capability and high temperature resistance has already convinced two of the five major PCB manufacturers in Europe: After extensive qualification, this innovative solder resist has come out on top at Würth Elektronik GmbH & Co. KG based in Niedernhall and RUWEL International GmbH of Geldern, Germany.
Elpemer® AS 2467 SM-DG is distinguished by a high level of compatibility with various equipment concepts: Würth Elektronik has opted for a spray coating unit by ahk Service & Solutions GmbH and a dryer of Beltron GmbH whereas RUWEL relies on the spray coater and dryer of all4-PCB AG.
The benefits of direct imaging can be fully exploited by Elpemer® AS 2467 SM-DG on the standard units of various equipment manufacturers, such as the direct imaging system Apollon 11 DI of Printprocess AG, Ledia of Dainippon Screen (SCREEN Graphic and Precision Solutions Co., Ltd.), MDI exposure unit of Schmoll Maschinen GmbH, Nuvogo™ 800 of Orbotech Ltd. and UV-P300 of Limata GmbH.
Very short exposure times combined with a high resolution allow perfect exposure results along with a high economic efficiency, not least due to the cost saving potential as a result of eliminated production, storage and handling of the film.
Moreover, this new product captivates by a simple and secure processability and a top quality of the final result.
Especially in industry and automotive electronics, increasing resistance against high temperatures and thermal shocks is demanded owing to the steadily rising levels of operating temperatures.
Here Elpemer® AS 2467 SM-DG plays another trump card withstanding thermal shock tests of more than 1000 cycles at -40/+175 °C without any cracking or loss of adhesion, and is therefore suitable for exposure to permanent temperature loads >1000 h up to 175 °C. This ensures a high reliability of the solder resist coating under the harsh conditions imposed by high temperature applications.
It should also be noted that silicone additives have been dispensed with in the formulation; such additives are often formulated to improve the spreading and the outgassing of the ink. It is understood that the youngest generation of Elpemer® products comes without the photo initiator Irgacure™ 907 (CAS-Nr.: 71868-10-5) which is subject to labelling.
The benefits of Elpemer® AS 2467 SM-DG have been summed up as follows by Gerard van Dierendonck, managing director of RUWEL: „RUWEL will process Elpemer® AS 2467 SM-DG in our spray coating unit in the future, in combination with the Dainippon Screen LEDIA direct imager. There are several criteria for RUWEL why we chose Elpemer® AS 2467 SM-DG: Besides the quality aspect such as resolution, high thermal cycling resistance for high temperature applications is of course essential, besides issues like processability, environmental compatibility and ease of handling (mixing of ink, size and weight of containers, return / disposal of containers). The last crucial point is of course exposure speed; here too, we can be more than satisfied at the moment since the exposure speed is up 25 % compared to competitive inks tested, which reflects of course directly in the throughput of the direct imaging system.”
Dr. Wolfer of Würth Elektronik GmbH & Co. KG has put their decision for Peters in a nutshell: “Thanks to the good co-operation and in particular owing to the special relationship with the development department, the introduction and qualification of the ink system at our new PCB facility in Niedernhall went very well. Peters is one of our long-standing and reliable partners offering best service.“
Undertaking substantial investments in state-of-the art processing technology for their solder resist processing, both Würth Elektronik GmbH & Co. KG in Niedernhall and RUWEL International GmbH have selected Elpemer® AS 2467 SM-DG as a modern and future-proof solder resist system.
For those PCB manufacturers equipped with different coating technology, screen printing, curtain coating and electrostatic spraying versions are available.”