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themselves are of lower molecular weight than a thermoplastic resin or polymer.Thermoset coatings develop their optimum mechanical properties and performancerequirements only when sufficient crosslinking reactions between the functionalgroups have occurred, which results in an increase in molecular weight.Resins or polymers or prepolymers or crosslinking agents or crosslinkingprepolymers or crosslinking resins are prepared only from monomers and otherstarting substances included in Annex II Lists A and B or are themselves on theselists.Thus it is necessary to describe how these substances are used to prepare relativelycomplex mixtures of resins or polymers or prepolymers as well as crosslinking resinsor crosslinking agents or crosslinking prepolymers. Due to their complexity, it isimpracticable to individually list all of the potential components present in the resinsor prepolymers or polymers or crosslinking agents or crosslinking prepolymers orcrosslinking resins mixed in the applied film. This is also the case for oligomers andisomers of substances in Lists A&B, even if some are relatively low molecular weightspecies. Thus to ensure uniformity of treatment for all resins or prepolymers orpolymers or crosslinking agents or crosslinking prepolymers or crosslinking resinsonly the building blocks for resins or polymers or prepolymers or crosslinking agentsor crosslinking prepolymers or crosslinking resins are listed. This informative Annexdescribes how these building blocks are combined and, as its name suggests, is forinformative purposes only. It is not exhaustive and in this context it is not a positivelist, but contains as much compositional information as is reasonably possible.Additives, including polymeric additives, cover a wide range of materials, many ofwhich are designed to improve the integrity of the final film. These would typically beflow aids, defoamers, plasticisers, whilst additives such as waxes are present toimprove the lubricity of the dried film. Waxes may also be used as a coating ratherthan an additive. In addition pigments could be present. Additives used are in AnnexIII Lists C and D or are polymeric being prepared from substances in Annex II Lists Aand B.The approach used in the informative annex consists of families of resins, furtherdefined by the types of substances in the inventory List of Monomers and otherstarting substances and Additives normally used in their manufacture and the typicalcombinations of the substances. An indication of the typical functional groups is alsogiven.The informative Annex consists of 2 sections in total:1. Overview of resins typically used2. Generic description of composition of typical resins, with functional groupspossibly present3. Overview of how the resins in 1 and 2 may be combined in a coating.32Europäische Vereinigung der Lack-, Druckfarben- und KünstlerfarbenindustrieEuropean Council of Paint, Printing Inks and Artists' Colours IndustryAvenue E. Van Nieuwenhuyse 4 - BE-1160 BrusselsTel:+32 (0)2 676 7480 - Fax: + 32 (0)2 676 7490 - E-mail: secretariat@cepe.org -Internet: http://www.cepe.org/