In addition to the solar fluxes EO-S-002 with 2 % solids and a very low resin content and the completely resin-free EO-S-007 with also 2 % solids content, which are in great demand on the market, Emil Otto is systematically expanding its portfolio for solar fluxes. In doing so, the flux specialist is pursuing a product strategy that provides the perfect product for every area of application, as Emil Otto has already implemented in the electronics industry and metal chemistry.

“For us, it is only logical to further expand the product area of solar fluxes, because we want to offer our customers products that are precisely tailored to the application, just like in the electronics industry,” says Markus Geßner, Marketing and Sales Manager at Emil Otto GmbH. For example, the newly developed EO-S-008 is similar in design to the EO-S-002, but belongs to the special fluxes, as it was developed for low-melting applications. In addition, the EO-S-008 can also be used for normal PV applications.

Furthermore, additional fluxes with different solid contents have been developed, such as the alcohol-based fluxes EO-S-009 and EO-S-010. The solid content here is 1.8 and 1.5 % respectively. “Due to the reduced solids content, the already very good residue behaviour can be noticeably improved once again, with very good soldering results. EO-S-010 also contains a very low and completely new resin complex,” Geßner continues. But also hybrid fluxes on an alcohol-water basis are new in the portfolio, such as the fluxes EO-S-011 and EO-S-012. Both fluxes have 2 % solids and a very low resin content. “EO-S-011 has an alcohol content of 60 %, EO-S-012 even only 15 %, which means it is not a hazardous material at all. Because of this, these fluxes also reduce transport costs, as well as the effort required for storage and handling within production,” Geßner explains. The alcohol components are composed in such a way that despite the reduced alcohol content, the fluxes are optimised for drying. Due to the reduced alcohol content, the two fluxes are very price-stable and largely decoupled from the permanently rising prices for alcohols. As usual, the soldering results and the residue behaviour are very good.

However, one new flux stands out, Geßner emphasises: “We are particularly proud of the EO-S-013. The alcohol-based flux with a solids content of 2.0 % is characterised by a special synthetic resin complex. The acid value is unusually low at 5.0 – 7.0. Therefore, the flux leaves almost no residue, with exceptionally good soldering results. ” Furthermore, EO-S-013 is characterised by its outstanding temperature stability.

All solar fluxes from Emil Otto have been developed for soldering solar modules, tabber and stringer material, as well as for connecting cells. Furthermore, the products are NO-CLEAN fluxes, which are formulated halogen-free. All fluxes leave no sticky residues. Process tests with well-known machine builders from the stringer technology sector prove this. Furthermore, the activators are specially designed for high temperatures which are required in the production of solar modules, without affecting the efficiency of the activators.