An oxetane compound, which has a polarized bond between carbon and oxygen, is a four-membered ring ether compound which exhibits a high reactivity. The compound has an excellent property of exhibiting a higher polymerization rate particularly in photo-induced or thermally induced cationic polymerization than an epoxy compound.
Moreover, unlike epoxy compounds which have mutagenicity, safety for the human body is a major characteristic of oxetane compounds.
Recently, studies on ring-opening reactions other than cationic polymerization have been advancing. For example, Kougyou Zairyou (Engineering Materials) Vol. 49, No. 6 pages 53-60 (2001) illustrates reactions of oxetane compound with acyl halide compound, thiol compound, phenol compound and carboxylic acid, and suggests possibility of a new heat-curable resin. Oxetane compounds are being much anticipated to be industrially used in a wider range.
Many other oxetane compounds have been reported. For instance, an oxetane compound having a bisphenol skeleton as substitution for epoxy resin (JP-A-11-130766), an oxetane compound having a fluorene skeleton (JP-A-2000-336082), an oxetane compound having a novolak skeleton (JP-A-2000-336133), an oxetane compound having a naphthalene skeleton (JP-A-2001-31664) and a polyfunctional oxetane compound having a biphenyl skeleton (JP-A-2001-31665) have been disclosed.
An oxetane compound having an ethylenically unsaturated group for the purpose of introducing an oxetanyl group into the side chain of a vinyl-based copolymer is disclosed (JP-A-7-17958 and JP-A-2000-26444).
Further, synthesis methods of a monomer having both an oxetanyl group and a (meth)acryl group are disclosed in JP-A-2000-63371, and JP-A-2003-201286, JP-A-2003-137878 and JP-A-2003-137877.