DIN EN 61249-2-43:2017-03

This part of IEC 61249 gives requirements for properties of non-halogenated epoxide cellulose paper reinforced core/woven E-glass reinforced surface laminate sheets of defined flammability (vertical burning test), copper-clad for lead-free assembly in thicknesses of 0,60 mm up to 1,70 mm. The flammability rating is achieved through the use of nonhalogenated fire retardants reacted as part of the epoxide polymeric structure. The glass transition temperature is defined to be 100 °C minimum. The requirements of some properties are divided into different performance classes. The class desired should be specified on the purchase order; otherwise the default class of material will be supplied. Halogen-free epoxy resin, with or without fillers, which allows the production of laminates with a glass transition temperature of at least 100 °C, shall be used. The total halogen content - based on resin plus reinforcing material - amounts to a maximum of 1,500 ppm, whereby the chloride and bromide content in each case amounts to a maximum of 900 ppm. Contrast agents may also be added to the laminate to improve processability, for example to increase contrast during automatic optical testing. Its flammability is determined by the flammability requirements. The copper surface shall be largely free of defects that could affect the suitability of the material for the intended application. The unclad side of a single-sided cladded sheet shall have the natural appearance resulting from the curing process. Minor color deviations are permissible. Furthermore, this side of the sheet shall have a gloss that is determined by the surface quality of the pressed sheets or release layers used. Deviations in gloss due to the pressure effect of the gases released during the curing process are permissible. The responsible committee is DKE/K 682 "Aufbau- und Verbindungstechnik für elektronische Baugruppen" ("Packaging and interconnection technology for electronic assemblies") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.