JP2599187B2 - Method of manufacturing composite striatum - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a composite filament which produces a composite filament using high-strength, low-elongation fibers.

[Prior art] The present applicant has developed a manufacturing technique for a composite filament which is made of high-strength and low-elongation fiber, is lightweight and has high tensile strength per sectional diameter, and has already applied for a patent. Yes
No. 62-18679).

The method for producing the composite filamentous body is to assemble fibers of high strength and low elongation such as carbon fibers into a fiber core, impregnate the fiber core with a thermosetting resin, and then dry the fiber core on its peripheral surface. A powder agent is adhered, and the fibers are densely braided around the outer periphery of the fiber core to cover the outer periphery. Thereafter, the thermosetting resin impregnated into the fiber core is heated and cured.

In such a manufacturing method, it is possible to prevent the thermoplastic resin impregnated in the fiber core from leaking to the outside by coating the outer periphery thereof, thereby obtaining a lightweight, high-strength composite filament having a high tensile strength per cross-sectional diameter. it can.

[Problems to be Solved by the Invention] By the way, when the thermosetting resin impregnated in the fiber core is cured by heating, the fiber core shrinks almost integrally with the thermosetting resin. The thermosetting resin impregnated in the core, there is a difference in heat shrinkage between the coating applied to the outer periphery of the fiber core, especially when the heat shrinkage of the coating is smaller than that of the thermosetting resin, When the thermosetting resin is cured by heating, the coating cannot follow the contraction of the fiber core, and as a result, a gap is generated between the fiber core and the coating or inside the fiber core,
It has been found that the required compactness of the composite filament decreases, and the cross-sectional shape also becomes non-uniform, which adversely affects the strength.

Therefore, a material having a heat shrinkage equivalent to that of the thermosetting resin impregnated into the fiber core may be selected as a constituent material of the coating. However, a composite filament that requires various characteristics according to the application is required. It is not advisable to select and change the material for the coating every time when manufacturing the product.

The present invention has been made by paying attention to such a point, and the purpose thereof is that even if there is a difference in heat shrinkage between the thermosetting resin and the coating, the coating follows the fiber core. Accordingly, it is an object of the present invention to provide a method for producing a composite filament which shrinks in such a manner and always adheres to the outer periphery of the fiber core.

[Means for Solving the Problems] In order to achieve such an object, the present invention bundles, twists, braids and the like high-strength low-elongation fibers such as carbon fibers, polyaramid fibers, glass fibers, and silicon carbide fibers. To form a fiber core, impregnating the fiber core with a thermosetting resin such as unsaturated polyester, epoxy, polyurethane, or polyimide, and then winding or braiding a coating material on the outer periphery of the fiber core. Applying a dense coating, then heating the fiber core and curing the thermosetting resin inside to obtain a composite striated body, when applying a coating to the outer periphery of the fiber core, An elongation corresponding to the heat shrinkage of the thermosetting resin impregnated in the fiber core is given.

[Function] Since the material of the coating applied to the outer periphery of the fiber core is given in advance an elongation corresponding to the heat shrinkage of the thermosetting resin impregnated in the fiber core, the fiber accompanying the curing of the thermosetting resin is provided. The outer peripheral coating shrinks to follow the shrinkage of the core, so that no void remains between the fiber core and the coating or inside the fiber core.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

Example 1 A fiber core a was formed by twisting 15 carbon fibers of 12000 into 1 unit and fifteen of them were twisted to form a fiber core a. The fiber core a was passed through a tank b containing an epoxy resin, and the epoxy resin was applied to the fiber core a. To
The fiber core a is impregnated with 40% by weight, and the fiber core a is formed into a required cross-sectional shape by passing it through a shaping die c, and excess resin is removed. Next, the fiber core a is passed through a tank d containing talc (dry powder), and talc is adhered to the peripheral surface thereof.

Thereafter, the fiber core a is passed through a wrapping device e, and eight 1000 denier polyester yarns which are aligned in parallel and closely contacted with each other are densely wound around the outer periphery of the fiber core a at a pitch of 5 mm to apply a coating f. At this time, in order to correct the difference in the thermal shrinkage between the epoxy resin impregnated in the fiber core a and the coating f,
While giving at least 2% elongation to the polyester yarn which is the material of the coating f at a tension of 400 g per 1000 deniers,
The polyester yarn is wound around the outer periphery of the fiber core a. Next, the fiber core a provided with the coating f was passed through a heating tank g,
Heating at 0 ° C. for 90 minutes completely cures the uncured epoxy resin inside the fiber core a to obtain a composite filament having a diameter of 4.5 mm.

The fiber core a shrinks with the curing of the epoxy resin, but since the material of the coating f has been previously stretched, the coating f
Also shrink so as to follow the fiber core a, so that no void remains between the fiber core a and the coating f or inside the fiber core a.

Example 2 In place of the coating f with the polyester yarn in Example 1, a coating f is formed by a braid of a 9 mm × 16 lead braid with 1000 denier polyester multi-yarn. At this time, in order to correct the difference in heat shrinkage between the epoxy resin impregnated in the fiber core a and the coating f, the polyester multi yarn as the material of the coating f is stretched by at least 2% at a tension of 2.5 kg per 1000 denier. And braiding. After that, the fiber core a provided with the coating f is heated at 180 ° C. for 90 minutes to cure the epoxy resin inside the fiber core a.

Example 3 Seven units of 23μ glass fiber 4450 tex (count) were bundled in a state of being aligned in parallel to form a fiber core a, and an unsaturated polyester resin was added to the fiber core a by 43% by weight.
After impregnation, the fiber core a is passed through a shaping die c to form a cross-sectional shape and remove excess resin. Further, talc is adhered to the peripheral surface thereof. The coating f is formed by densely winding at a pitch of 5 mm and a polyester tape having a width of 15 mm and a width of 20 mm. At this time, in order to correct the difference in thermal shrinkage between the unsaturated polyester resin impregnated in the fiber core a and the coating f, the polyester tape as the material of the coating f is stretched at least 3% with a tension of 550 g at a tension of 550 g. Wrap. And after this, the fiber core g with the coating f
Is heated at 130 ° C. for 90 minutes to cure the unsaturated polyester resin inside the fiber core a to obtain a composite filament having a diameter of 6.2 mm.

In any of the examples, in a state where the internal thermosetting resin remains uncured, a plurality of composite filaments are braided or twisted into a rope shape, and this is passed through a heating tank. The case where the thermosetting resin is cured may be used.

[Effects of the Invention] As described above, according to the present invention, when a coating is applied to the outer periphery of a fiber core, elongation corresponding to the heat shrinkage of the thermosetting resin is given to the material of the coating in advance. Therefore, even if there is a difference in the heat shrinkage between the thermosetting resin and the coating, the coating shrinks so as to follow the shrinkage of the fiber core and always adheres to the outer periphery of the fiber core. No void remains between the coating and the coating or inside the fiber core, and a composite filament having a high density and a uniform cross-sectional shape can be obtained.

[Brief description of the drawings]

FIG. 1 is a process diagram showing a production process of a composite filament, and FIG. 2 is a plan view of the composite filament.

Claims (1)

(57) [Claims] 1. A fiber core is formed by gathering high strength and low elongation fibers by means such as bundling, twisting and braiding, and impregnating the fiber core with a thermosetting resin. A dense coating is applied by winding or braiding the coating material, and thereafter, the fiber core is heated to cure the thermosetting resin inside to obtain a composite filament, and the outer periphery of the fiber core is coated. A method for producing a composite filament, wherein the material of the coating is given in advance an elongation corresponding to the heat shrinkage of the thermosetting resin impregnated in the fiber core.