JP6897705B2 - Reinforcing fiber woven fabric and its manufacturing method - Google Patents

Description

The present invention relates to a unidirectional reinforcing fiber woven fabric that exhibits excellent properties for a fiber reinforced composite material and a method for producing the same, and is particularly suitable for a unidirectional reinforcing fiber for civil engineering and construction and general industrial use. Regarding textiles and their manufacturing methods.

Conventionally, reinforcing fiber woven fabrics that exhibit excellent physical properties for fiber-reinforced composite materials have been widely used as reinforcing materials for concrete structures for civil engineering. Especially in the field where strength is required, a reinforced fiber sheet-like material using a reinforced fiber material such as aramid fiber or carbon fiber is often used. For example, Patent No. 3279049 and Patent No. 3019004 propose a reinforcing fiber woven fabric using carbon fiber threads for repairing and reinforcing concrete structures such as bridges, tunnels, chimneys and buildings, and are used for the woven fabric. Most of the carbon fiber yarns are woven using general-purpose carbon fiber yarns having 12,000 filaments. In addition, the basis weight of these proposed woven fabrics is mainly relatively low basis weight woven fabrics of around ^{300 g / m 2.} However, in the conventional carbon fiber reinforced plastic, for example, thin carbon fiber threads having 3000 filaments are arranged in the warp direction and the weft direction or the warp direction, and the carbon fiber texture is 200 to 400 g / m ^{2 in} a thin unidirectional or vertical direction. Since a large number of prepregs impregnated with resin in advance are laminated using a bidirectional woven fabric and cured in an autoclave to be molded, (1) the carbon fiber threads are thin, so the productivity of the carbon fiber threads is low. , (2) The productivity of the woven fabric is low because the woven fabric is manufactured with fine threads.
(3) Since the texture of the woven fabric is thin, the number of layers to be laminated increases to a predetermined thickness, which increases the time and effort for laminating. (4) Since the prepreg process is required, the manufacturing cost of the prepreg is added. (5) Resin There was a problem that an autoclave was required to cure the resin and a large capital investment was required.
In recent years, in order to solve these problems, Japanese Patent No. 3991439 and Japanese Patent No. 3991440 have been proposed as reinforcing fiber woven fabrics using thick carbon fiber threads called Rajito.
Patent No. 3991439 has a basis weight of 400 to 700 g / m ² , and Patent No. 3991
No. 440 proposes a very high basis weight woven fabric with a basis weight of 450 to 1500 g / m ^2. In order to obtain a relatively high basis weight fiber reinforced plastic for industrial use, such a high basis weight reinforced fiber woven fabric is effective. However, for example, since the reinforcing material of the concrete structure for civil engineering is hand lay-up molding, the impregnation property of the resin is deteriorated in the high-grained woven fabric. A woven fabric with a relatively low grain size of ^{2 or less is desired.}

Japanese Patent No. 3279049 Japanese Patent No. 3019004 Japanese Patent No. 3991439 Japanese Patent No. 3991440

The present invention provides an inexpensive carbon fiber woven fabric which is excellent in impregnation property of a resin for hand lay-up molding and excellent mechanical properties when molded even when a thick carbon fiber yarn is used, and a method for producing the same. is there.

That is, the present invention
[1] A unidirectional reinforcing fiber woven fabric in which a large number of carbon fiber multifilament yarns are arranged on the warp yarns and auxiliary fiber yarns thinner than the carbon fiber multifilament yarns are arranged on the weft yarns.
The number of filaments of the carbon fiber multifilament yarn is 50,000 to 100,000, or the total fineness of the carbon fiber multifilament yarn is 33,000 to 74250 decitex, and the carbon fiber multifilament yarn in the state of forming a woven fabric. It is a unidirectional reinforcing fiber woven fabric for hand lay-up molding, characterized in that the yarn width is 10 mm or more and the woven fabric texture is 200 g / m ^{2 or less.}
[2] A plurality of weft auxiliary fibers that form a carbon fiber thread group without substantially bending the carbon fiber multifilament thread and intersect the carbon fiber thread group on both sides of the carbon fiber thread group. It has a weft auxiliary fiber yarn group composed of yarns, and further has a warp yarn auxiliary fiber yarn group composed of a plurality of warp yarn auxiliary fiber yarns, and the weft yarn auxiliary fiber yarn group and the warp direction auxiliary fiber yarn group form a weaving structure. The directional reinforcing fiber woven fabric for one-hand lay-up molding according to claim 1, wherein the carbon fiber filaments are integrally held.
[3] The carbon fiber multifilament yarn and / or the warp auxiliary fiber yarn is adhered by a thermoplastic polymer continuously attached to the weft auxiliary fiber yarn at an intersection with the weft auxiliary fiber. The unidirectional reinforcing fiber woven fabric for hand lay-up molding according to claim 1 or 2.
[4] Unidirectionality composed of carbon fiber multifilament yarns arranged parallel to the warp direction
It is a method for manufacturing a reinforcing fiber woven fabric, and the number of filaments of the carbon fiber multifilament yarn is
The total fineness of the carbon fiber multifilament yarn is 330 to 50,000 to 100,000.
It is 00 to 74250 decitex, and the basis weight of the fabric is 300 g / m ² or less.
The carbon fiber multifilament yarn is widened, and the inner diameter width of the mail portion is 10 mm or more.
The carbon fiber multifilament yarn is opened using a heald, and the carbon fiber multifilament is used.
A method for producing a unidirectional reinforcing fiber woven fabric, which comprises heating a lament yarn or a woven fabric.
To.

According to the present invention, even if a thick carbon fiber thread is used, an inexpensive carbon fiber reinforced woven fabric having excellent impregnation property of a hand lay-up molded resin and excellent mechanical properties when molded can be obtained.

It is a figure which shows an example of the schematic structure of the loom that can be used in this invention. It is the schematic which shows an example of the shape of the heald used in this invention. It is an example of the perspective view of the unidirectional reinforcing fiber woven fabric obtained by this invention. It is an example of the perspective view of the unidirectional reinforcing fiber woven fabric obtained by this invention.

(Reinforcing fiber)
The carbon fiber multifilament yarn used in the present invention has 50,000 to 100 filaments.
It is a carbon fiber yarn with 000 yarns and a yarn fineness of 33,000 to 74250 decitex.
Further, it is preferable to use carbon fibers having a tensile strength of 3000 to 6000 MPa as a fiber reinforced plastic for general industrial use. In the present invention, the tensile strength of carbon fibers refers to the strand strength measured in accordance with JIS R7601.

The carbon fiber used in the present invention contains 0.01 to 5 mass of a substance having one or more functional groups selected from an epoxy group, a hydroxyl group, an amino group, a carboxyl group, a carboxylic acid anhydride group, an acrylate group and a methacrylate group. It can be used as a sizing agent that improves the convergence of fiber bundles and the adhesiveness between carbon fibers and matrix resin when made into fiber reinforced plastic.

(Weft auxiliary fiber thread)
As the weft auxiliary fiber yarn used in the present invention, any organic fiber or inorganic fiber thinner than the carbon fiber multifilament yarn which is a reinforcing fiber can be used. The weft auxiliary fiber yarn is 10
It is preferable to use glass fiber threads of 0 tex or less. In order to fix the carbon fiber multifilament yarn and / or the warp auxiliary yarn, it is preferable to continuously and linearly attach the thermoplastic polymer to the glass fiber yarn and use it as the weft auxiliary yarn. The method of attaching the thermoplastic polymer to the glass fiber yarn is not limited to twisting, covering, aligning and the like.

(Warp yarn auxiliary fiber yarn)
The fineness of the warp auxiliary fiber yarn used in the present invention is preferably 1/3 or less of that of the carbon fiber multifilament yarn which is a reinforcing fiber.

(One-way reinforced fiber woven fabric)
The unidirectional reinforcing fiber woven fabric of the present invention comprises a large number of carbon fiber multifilament yarns which are warp yarns and weft auxiliary fiber yarns.

Further, in the unidirectional reinforcing fiber woven fabric of the present invention, a large number of carbon fiber multifilament yarns, which are warp yarns, form a carbon fiber yarn group without substantially bending, and the carbon fiber yarn group is covered on both sides. It has a weft auxiliary fiber yarn group composed of a plurality of weft auxiliary fiber yarns intersecting with a carbon fiber yarn group, and further has a warp yarn auxiliary fiber yarn group composed of a plurality of warp yarn auxiliary fiber yarns. It is preferable that the warp auxiliary fiber yarn group forms a woven structure and integrally holds the carbon fiber yarn group.

In order not to bend the carbon fiber yarn group, a yarn thinner than the carbon fiber multifilament yarn is used as the warp auxiliary fiber yarn, and the warp auxiliary fiber yarn group and the weft auxiliary fiber yarn group form a woven structure.
It is preferable that the warp auxiliary yarns are bent and alternately intersected with the weft auxiliary yarns.

Further, in the unidirectional reinforcing fiber woven fabric of the present invention, a large number of carbon fiber multifilament yarns and / or warp auxiliary fiber yarns, which are warp yarns, are continuously attached to the weft auxiliary fiber yarns at the intersection with the weft auxiliary fiber yarns. It is preferable that the fibers are adhered to each other.

According to the unidirectional reinforcing fiber woven fabric of the present invention, the so-called bulk density of the woven fabric is smaller than that of the woven fabric obtained by using the conventional fine carbon fiber threads, with a grain ^{size of 300 g / m 2 or less.} 0
.. A woven fabric having a weight of about 6 g / cm ^{3 can be easily obtained.} No bulk density in Japanese Patent No. 3991439
.. A carbon fiber woven fabric having a basis weight of 65 g / cm ³ or less is mentioned, but it is a high basis weight woven fabric having a basis ^{weight of 400 g / m 2 or more.}
Here, the bulk density is calculated by the following formula.
Bulk density = W / (t × A)
However,
t: Thickness of woven fabric (cm)
A: Area of woven fabric (cm ² )
W: Carbon fiber mass (g) in the area A of the woven fabric

(Woven fabric manufacturing method)
The method for producing a woven fabric of the present invention is characterized in that a fiber opening step is incorporated during weaving. In order to obtain a low-grained woven fabric with carbon fiber multifilament yarns having 50,000 or more filaments, the number of carbon fiber yarns used is small, so the yarn width of each carbon fiber yarn constituting the woven fabric is widened to 10 mm or more. Otherwise, a woven fabric with few openings cannot be obtained. If the thread width of the carbon fiber threads is 10 mm or less, the opening of the woven fabric becomes large, the appearance quality is poor, and the resin pools after molding have an adverse effect on the mechanical properties of the fiber-reinforced composite material. The woven fabric with is good.

A plurality of carbon fiber multifilament yarns supplied by wefting from a reel (not shown) are uniformly sheeted by a back tension roll 1 and subsequently led to a scraping roll 2. In the present invention, it is essential to use the scraping roll. This is because it is necessary to sufficiently open and widen the carbon fiber multifilament yarns arranged as warp yarns in order to obtain a woven fabric having a low basis weight and no opening. The method of passing through the scraping roll is not particularly limited, such as a method of passing through a mountain shape as shown in FIG. 1 or a method of providing a plurality of scraping rolls in parallel and passing the upper and lower sides of each scraping roll alternately. Further, it is preferable that each scraping roll does not rotate. Further, by using a heating device in combination with the scraping roll, or by injecting hot air into the roll portion and further providing a vibrating device in combination, it is possible to greatly widen the carbon fiber multifilament yarn. In any case, it is more preferable to use the device necessary for widening the spread fiber according to the required purpose. However, if any of the above-mentioned spreading and widening methods is excessively applied, there is a risk of fluffing and impairing the mechanical properties of the reinforcing fibers. Therefore, it is preferable to appropriately select a method that does not cause a problem.

Next, the plurality of carbon fiber multifilament yarns that were opened and widened were driven and conveyed in roll groups 3 to 6.
And is led to Held 8 via Dansaroll 7. When the warp auxiliary fiber yarn is used for the unidirectional reinforcing fiber woven fabric, the warp auxiliary fiber yarn is also guided to the heald 8.

In the present invention, the width of the carbon fiber multifilament yarn widened by the scraping roll 2 is wound with a cloth.
Ideally, the yarn is held up to the lever 12, but due to the structure of the loom, the yarn width is always converged by the opening motion and the reed motion by the heald. Therefore, it is necessary to finally hold the yarn width equal to or larger than the required yarn width when passing through the heald 8. However, even if the fiber is sufficiently widened, it tends to be converged during the process due to the influence of the tension of the warp yarn and the inner diameter width of the mail portion of the heald being equal to or less than the yarn width. Such a tendency of convergence is to weave the warp yarn tension after the drive transport roll with the lowest possible tension, and to determine the inner dimension diameter width d (shown in FIG. 2) of the mail portion of the heald through which the carbon fiber multifilament yarn is passed. It can be suppressed by making it 10 mm or more. The height of the inner dimension is not particularly limited, but is preferably 2 mm or less.

Next, after passing through the reed, weft auxiliary fiber threads (not shown) to which a thermoplastic polymer is attached are opened with a heald in the openings between the carbon fiber multifilament yarn and the carbon fiber multifilament yarn, or the carbon fiber multifilament. A woven fabric is formed by reeding by inserting into the opening between the yarn and the warp auxiliary fiber yarn.

Subsequently, the rolls 10 to 11 and the cloth winding roll 12 are sequentially wound. When the weft auxiliary fiber yarn and the warp yarn are heat-sealed by a thermoplastic polymer attached to the weft auxiliary fiber yarn, the guide roll can be heat-sealed by contacting the guide roll as a heating roll. Further, a method of providing a non-contact heater such as an infrared heater for heat fusion may be used. It is desirable that the heat fusion is performed after the reed beating and before the cloth winding roll, but it is also possible to perform the heat fusion during the rewinding work of the wound woven fabric.

Examples will be described below.
(Example 1)
50K (number of filaments: 50,000) multifilament yarn made of carbon fiber (Pyrofil (product name) manufactured by Mitsubishi Rayon Co., Ltd.) is used for the warp yarn, and 22.5t.
A plain weave structure is formed using auxiliary fibers in which heat-sealing fibers (manufactured by Toray Co., Ltd.) are attached to ex glass fibers (manufactured by Unitika Glass Fiber Co., Ltd.) as weft auxiliary fiber yarns, and the texture is 200 g.
A unidirectional reinforcing fiber woven fabric of / m ² was produced, and the woven fabric opening ratio and the straightness of the carbon fiber threads of the obtained woven fabric were evaluated. The inner diameter width of the mail part of the used heald is 18.8 mm.
In the obtained woven fabric, the carbon fibers arranged in one direction are straight, and the weft auxiliary fiber yarn and the carbon fiber are adhesively solidified, and the reinforcing fiber woven fabric has few voids and is sufficiently opened. there were. In addition, work handleability was also good.
The woven fabric aperture ratio referred to here is a numerical value representing the area of the opening between the carbon fibers per woven fabric 10 cm × 10 cm as a ratio to the area of the woven fabric 10 cm × 10 cm, and light is irradiated from the lower part of the woven fabric. The transmission of the light to the woven fabric is image-processed and calculated by the following formula.
Aperture ratio = sum of opening area / 100 cm ² x 100 (%)
Next, the obtained unidirectional reinforcing fiber woven fabric 1ple was impregnated with XL-800 epoxy resin manufactured by Mitsubishi Resin Co., Ltd. to prepare a cured plate by a hand lay-up molding method, and a CF of JIS K7073 was prepared.
The tensile breaking strength was evaluated according to the tensile test method of RP. The results are shown in Table 1.

(Example 2)
A unidirectional reinforced reinforced fiber woven fabric having a ^{basis weight of 300 g / m 2} was produced and evaluated using the same thread usage as in Example 1. The results are shown in Table 1.
The inner diameter width of the heald used in this embodiment is 12.5 mm. The obtained woven fabric was a reinforced reinforced fiber woven fabric having less voids and sufficiently opened fibers and having a good appearance quality, although the carbon fiber was slightly less straight than the woven fabric obtained in Example 1. In addition, work handleability was also good.

(Comparative Example 1)
12K (number of filaments: 12000) multifilament yarn made of carbon fiber (Pyrofil (product name) manufactured by Mitsubishi Rayon Co., Ltd.) is used for the warp, and 22.5t.
A plain weave structure is formed using auxiliary fibers in which heat-sealing fibers (manufactured by Toray Co., Ltd.) are attached to ex glass fibers (manufactured by Unitika Glass Fiber Co., Ltd.) as weft auxiliary fiber yarns, and the texture is 200 g.
A unidirectional reinforcing fiber woven fabric of / m ^{2 was produced and evaluated.} The results are shown in Table 1.

From the above, by weaving using the weaving method of the present invention using thick carbon fiber yarns, a high-quality low-mesh fabric with a small opening and a stable yarn width can be produced at low cost even though it is a low-mesh fabric. be able to. Moreover, the fiber-reinforced composite material obtained from the unidirectional reinforcing fiber woven fabric of the present invention clears the spec value of 3400 MPa of the material used as the current reinforcing sheet in the civil engineering field in terms of mechanical properties. Extremely useful industrially.

Claims (3)

A unidirectional reinforcing fiber woven fabric in which a large number of carbon fiber multifilament yarns are arranged on the warp yarn and auxiliary fiber yarns thinner than the carbon fiber multifilament yarn are arranged on the weft yarn, and the filament of the carbon fiber multifilament yarn is arranged. The number is 50,000 to 100,000, or the total fineness of the carbon fiber multifilament yarn is 33,000 to 74250 decitex.
One-way reinforcement for hand lay-up molding, characterized in that the yarn width of the carbon fiber multifilament yarn in the state of forming the woven fabric is 10 mm or more and the texture of the woven fabric is 200 g / m ^{2 or less.} Textile fabric. The carbon fiber multifilament yarn constitutes a carbon fiber yarn group without substantially bending, and is composed of a plurality of weft auxiliary fiber yarns intersecting the carbon fiber yarn group on both sides of the carbon fiber yarn group. It has a weft auxiliary fiber yarn group, and further has a warp yarn auxiliary fiber yarn group composed of a plurality of warp yarn auxiliary fiber yarns, and the weft yarn auxiliary fiber yarn group and the warp direction auxiliary fiber yarn group form a woven structure and form the carbon fiber yarn. Handoreia' according to Article groups to claim 1, characterized in that it is held together
Unidirectional reinforcing fiber woven fabric for molding. Claimed that the carbon fiber multifilament yarn and / or the warp auxiliary fiber yarn is adhered by a thermoplastic polymer continuously attached to the weft auxiliary fiber yarn at an intersection with the weft auxiliary fiber. Item 2. The unidirectional reinforcing fiber woven fabric for hand lay-up molding according to Item 1 or 2.

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