초록 ▼

A method for the preparation of prepregs comprises (i) exposing to actinic radiation a layer of a liquid composition containing an epoxide resin, a photopolymerizable compound and a heat-activated curing agent for epoxide resins until the said composition solidifies to form an essentially solid cont

A method for the preparation of prepregs comprises (i) exposing to actinic radiation a layer of a liquid composition containing an epoxide resin, a photopolymerizable compound and a heat-activated curing agent for epoxide resins until the said composition solidifies to form an essentially solid continuous film due to photopolymerization of the said photopolymerizable compound while the epoxide resin remains substantially in the thermosettable state, and (ii) bringing together the film so formed and fibrous reinforcing material under conditions such that the said film flows about the fibers and the components of the said film and the fibers form a coherent structure. Preferably the liquid composition also contains a dual-functional substance which has in the same molecule both an epoxide group and a dissimilar group through which the substance can be photopolymerized. The prepreg, optionally after shaping and/or heating, is heated to cure the epoxide resin and, if used, the photopolymerized dual-functional substance.

대표청구항 ▼

A method for the preparation of prepregs which comprises (i) exposing to actinic radiation a layer of a liquid composition containing (a) an epoxide resin (b) a photopolymerisable compound, the molar ratio of a:b being from 10:1 to 1:10, and (c) a heat-activated curing agent for epoxide resins, unti

A method for the preparation of prepregs which comprises (i) exposing to actinic radiation a layer of a liquid composition containing (a) an epoxide resin (b) a photopolymerisable compound, the molar ratio of a:b being from 10:1 to 1:10, and (c) a heat-activated curing agent for epoxide resins, until the said composition solidifies to form an essentially solid continuous film due to photopolymerisation of the said photopolymerisable compound while the epoxide resin remains substantially in the thermosettable state, and (ii) bringing together the film so formed and fibrous reinforcing material under conditions such that the said film flows about the fibers and the components of the said film and the fibers form a coherent structure.