초록 ▼

A novel method for producing thick composite parts based upon photopolymerizable compositions is disclosed. The constituents of the photopolymerizable mixture comprise a monomer or monomers capable of polymerizing by free radical or cationic mechanisms, and a photoinitiator system which possesses an

A novel method for producing thick composite parts based upon photopolymerizable compositions is disclosed. The constituents of the photopolymerizable mixture comprise a monomer or monomers capable of polymerizing by free radical or cationic mechanisms, and a photoinitiator system which possesses an absorbance characteristic which is effectively reduced, or self-eliminating, upon initiation of the polymerization reaction. Parts having thicknesses up to 2 cm and thicker for varying end use applications are made by photopolymerizing such compositions. In addition, using such compositions composite parts can be made using a reinforcement material such as a glass fiber mat present in an amount by weight of from about 5 to about 70%.

대표청구항 ▼

[ We claim:] [1.] A method for making a part having a defined thickness comprising providing a photopolymerizable composition including at least one monomer to be photopolymerized to a polymer and a photoinitiator having a self-eliminating absorbance and present in an amount sufficient to initiate t

[ We claim:] [1.] A method for making a part having a defined thickness comprising providing a photopolymerizable composition including at least one monomer to be photopolymerized to a polymer and a photoinitiator having a self-eliminating absorbance and present in an amount sufficient to initiate the photopolymerization of the monomer present while allowing the absorbance to self-eliminate, said monomer not having unduly facile extractable hydrogens so as to adversely affect the photopolymerization and said monomer and polymer having minimal absorbance in the wavelength range where photopolymerization is initiated so that the absorbance of said photoinitiator is allowed to self-eliminate, providing a light source for emitting light in the ultraviolet wavelength range to excite the photoinitiator so as to initiate said photopolymerization, providing a mold having a cavity in the shape of said part and at least one side thereof allowing the light emitted from said light source to penetrate into the cavity of the mold, initiating operation of the light source to cause light to be emitted, filling said mold with said photopolymerizable composition, positioning said mold and said light source such that the light being emitted from said light source penetrates into the cavity of said mold, exposing the photopolymerizable composition to the light emitted for a time adequate to cure said composition throughout the thickness of the part being formed as the absorbance of the photoinitiator self-eliminates as the curing proceeds, and removing the part from the mold cavity.