Abstract: A light-transmitting laminated panel having increased resistance to impact-induced rupture sequentially includes: a) a glass layer, b) an optically clear layer of a plasticized polyvinyl butyral matrix containing discrete particles of crosslinked polyvinyl butyral integrally randomly dispersed throughout the matrix which enhance the impact-resistance of the panel and are visually indistinguishable from the matrix polyvinyl butyral, and c) another glass layer, the laminated panel at a specific pummel adhesion having greater mean break height than that of a laminated panel containing layers a), b) and c) but without the impact-resistance-enhancing particles of crosslinked polyvinyl butyral in layer b). An amount up to 40 weight % of the particles is incorporated into the matrix polyvinyl butyral before preparing the laminated panel.

Abstract: A laminated glazing unit having improved impact strength comprising a), b) and c) in sequence: a) a glass layer; b) a plasticized layer containing partial polyvinyl butyral; c) another glass layer; and d) means, preferably a multiplicity of spaced projections, dispersed on the surface of at least one of the foregoing layers, preferably the plasticized layer, capable of resisting adhesion to the layer with which it is in contact, the area without said dispersed means (e.g. between projections) of the layer having such dispersed means having high affinity for adhesion to the layer with which it is in contact, such laminated glazing at a specific pummel adhesion having a greater mean break height than that of a laminated glazing containing layers a) b) and c) but without d). The dispersed means may be on the surface of a glass layer but is preferably on the plasticized layer.