Лако-красочные материалы — производство

In general, polymers are not very harmful — or not even harmful at all — at least for short-term human contact, as long as they are present in the form of solid substances within the adhesive layers. However, if the adhesive contains low-molecular sub­stances before the setting process takes place, then the hazard potential may be deemed greater. The same applies to the handling of solvent-containing contact adhesives, and to chemically setting systems in particular. In the noncured state these are often chemically reactive, while some components may even be toxic, such as the amine hardeners of epoxy resins, isocyanate curing agents of polyurethane, and acrylates of the second generation. Besides respiratory toxicity, in some cases an allergic sensitization or hazard of strong caustic reactions may be expected on direct skin contact. Likewise, monomeric or low-molecular substances may be easily dispersed, which may result in an increased hazard potential. Due to the reactivity and potential dispersion risk (most likely in the form of vapors), a regulation specifies that, in the noncured state, chemically reactive adhesives should be treated as special hazardous refuse, while cured adhesives are considered as household refuse.

Low-molecular organic systems also present a greater fire hazard than do polymer materials. At present, classification rules have been introduced for toxicity, ecological hazard potential and fire hazard, the details of which must be specified by the adhesive manufacturer in standardized data sheets.

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