Adhesive compositions are rendered stable against degradation caused by
ultraviolet light through the incorporation of a highly soluble,
photostable benzotriazole UV absorber which is substituted in the ortho
position of the hydroxyphenyl ring by .alpha.-cumyl or phenyl. Examples of
such compounds are
2-(2-hydroxy-3-.alpha.-cumyl-5-tert-octylphenyl)-2H-benzotriazole,
5-chloro-2-(2-hydroxy-3-.alpha.-cumyl-5-tert-octylphenyl)-2H-benzotriazole
,
5-fluoro-2-(2-hydroxy-3-.alpha.-cumyl-5-tert-octylphenyl)-2H-benzotriazole
, 2-(2-hydroxy-3-.alpha.-cumyl-5-tert-butylphenyl)-2H-benzotriazole,
5-chloro-2-(2-hydroxy-3-.alpha.-cumyl-5-tert-butylphenyl)-2H-benzotriazole
and
5-fluoro-2-(2-hydroxy-3-.alpha.-cumyl-5-tert-butylphenyl)-2H-benzotriazole
. These compounds exhibit excellent photostability and are highly soluble
in adhesive formulations. The laminated articles derived from these
compositions include, for example, solar control films, films and
glazings, UV absorbing glasses and glass coatings, windscreens,
retroreflective sheetings and signs, solar reflectors, optical films and
the like.
Le composizioni adesive sono rese stabili contro degradazione causata da luce ultravioletta con l'incorporazione di un assorbitore UV del benzotriazolo altamente solubile e photostable che si sostituisce nell'orto posizione dell'anello di hydroxyphenyl da alpha.-cumyl o da fenile. Gli esempi di tali residui sono 2-(2-hydroxy-3-.alpha.-cumyl-5-tert-octylphenyl)-2H-benzotriazole, 5-chloro-2-(2-hydroxy-3-.alpha.-cumyl-5-tert-octylphenyl)-2H-benzotriazole, 5-fluoro-2-(2-hydroxy-3-.alpha.-cumyl-5-tert-octylphenyl)-2H-benzotriazole, 2-(2-hydroxy-3-.alpha.-cumyl-5-tert-butylphenyl)-2H-benzotriazole, 5-chloro-2-(2-hydroxy-3-.alpha.-cumyl-5-tert-butylphenyl)-2H-benzotriazole e 5-fluoro-2-(2-hydroxy-3-.alpha.-cumyl-5-tert-butylphenyl)-2H-benzotriazole. Questi residui esibiscono il photostability eccellente e sono altamente solubili nelle formulazioni adesive. Gli articoli laminati hanno derivato da queste composizioni includono, per esempio, le pellicole solari di controllo, pellicole e glazings, rivestimenti di vetro assorbenti UV e di vetro, tergicristalli, sheetings e segni a riflessione catottrica, riflettori solari, pellicole ottiche e simili.
