초록 ▼

An improved multifilamentary fibrous material is formed having solid particles of a matrix-forming thermosetting resin substantially uniformly dispersed among adjoining filaments in the absence of fusion bonding. The thermosetting resin particles initially are dispersed in an aqueous medium containi

An improved multifilamentary fibrous material is formed having solid particles of a matrix-forming thermosetting resin substantially uniformly dispersed among adjoining filaments in the absence of fusion bonding. The thermosetting resin particles initially are dispersed in an aqueous medium containing an effective amount of a dissolved polymeric binding agent and the viscosity of the medium subsequently is substantially increased to at least 50,000 cps. to form a gelled impregnation bath having a plastic flow characteristic with shear-thinning behavior wherein the thermosetting resin particles are substantially uniformly suspended. The resulting impregnation bath is caused to flow between the adjoining filaments of the multifilamentary fibrous material with a concomitant viscosity reduction which aids in the incorporation of the resin particles. The concentration of the aqueous medium in the product is controlled to yield a uniform, handleable, drapable, tacky, and highly stable product. Upon the application of heat and pressure the improved product can be transformed into a fiber-reinforced composite article wherein the thermosetting resin forms the matrix phase.

대표청구항 ▼

An improved preimpregnated fibrous material suitable for the formation of a fiber-reinforced composite article, said preimpregnated fibrous material comprising (a) a plurality of adjoining substantially parallel reinforcing filaments and, substantially uniformly dispersed between adjoining filaments

An improved preimpregnated fibrous material suitable for the formation of a fiber-reinforced composite article, said preimpregnated fibrous material comprising (a) a plurality of adjoining substantially parallel reinforcing filaments and, substantially uniformly dispersed between adjoining filaments in the absence of fusion bonding, (b) an effective amount of a polymeric water-soluble binding agent, (c) aqueous medium, and (d) solid particles of thermosetting resin, said (b), (c) and (d) having been derived from a dispersion having a viscosity specifically selected to provide a preimpregnated fibrous material which inherently (1) is drapable and tacky at ambient conditions, (2) is handleable without segregation of said particles within the fibrous material and (3) capable upon the application of heat and pressure of being transformed into a substantially void-free composite article of a predetermined configuration wherein said thermosetting resin is substantially completely cured and forms the matrix phase.