JP5505597B2 - Modified cross section glass fiber - Google Patents

Description

  The present invention relates to a modified cross-section glass fiber having a flat cross-sectional shape perpendicular to the spinning direction, and a technique for improving the method of manufacturing the modified cross-section glass fiber.

  Many glass fibers made of inorganic glass are used to reinforce various organic resin materials, but diversification of resin materials used as structural materials that require high strength in recent years and their use in a wide range of applications Along with this, the performance required for composite resin materials has become even more sophisticated and difficult. For this reason, many novel composite materials that satisfy various requirements that have not been heretofore have been invented.

  In such a situation, glass fibers constituting the composite material are newly required to have various performances as in the case of the resin material, and many inventions related thereto have been made. For example, in Patent Document 1, when glass fiber is used as a reinforcing material, mechanical properties such as bending strength, bending elastic modulus, or Izod impact strength and shrinkage ratio are improved as the glass fiber filling amount increases. On the other hand, the problem that the material anisotropy becomes large is described, and in order to solve this problem, an orifice plate that surrounds the orifice outlet and has a convex edge extending below the bottom surface of the orifice plate is used. Thus, an invention relating to a glass fiber having a non-circular cross section having a cross section surrounded by a plurality of straight lines and a plurality of curves is disclosed.

  Further, Patent Document 2 describes the cross-sectional shape of the glass fiber for the purpose of reducing the variation in the molded product of the resin material containing the glass fiber and improving the dimensional stability in both the flow direction and the perpendicular direction. A curve having a plurality of radii of curvature, and a maximum radius of curvature of a curve having a plurality of radii of curvature with respect to a curve having a minimum radius of curvature among the curves having a plurality of radii of curvature. An invention is disclosed that can be realized by forming a shape surrounded by a curve composed of a plurality of curvature radii of 3 or more in the ratio of the curvature radii of the curve having.

  Patent Document 3 describes a nozzle tip for the purpose of improving the problem of easy breakage when spinning flat glass fibers having a flatness ratio of 2.0 or more at a high speed of 1500 m / min or more. Use a nozzle tip with a molten glass pool on the top of the orifice hole with a minor axis to major axis ratio of 1: 2.5 or more provided on the bottom, and a flat ratio (major axis / minor axis) of 2.5 or more. Thus, there is disclosed an invention for forming a flat glass fiber in which a cross-sectional area of the flat glass is 85% or more with respect to a rectangular area in which the obtained flat glass fiber cross section is inscribed.

JP 7-126033 A JP 7-133132 A JP 2000-103635 A

  However, the inventions that have been made so far are not sufficient as glass fibers used as a composite material for precision-shaped electronic components that require strict dimensional accuracy. In addition, the glass fibers of Patent Documents 1 to 3 that have been invented in the past improve the anisotropy of the shrinkage in the vertical and horizontal directions when the filling rate of the glass fibers in the composite state increases. The anisotropy can be improved to some extent, but it still does not fully satisfy the requirements. That is, when conventional glass fibers are used, the strength when stress perpendicular to the orientation direction acts on the surface perpendicular to the direction in which the glass fiber bundles are oriented results in anisotropy with other directions. And the isotropy of strength is easily impaired.

  As a method for improving the strength anisotropy, there are a method using a mixture of a plurality of glass fibers and a method using a milled fiber, both of which are limited in use because of a decrease in strength. There are some restrictions, and it does not satisfy more various requests.

  In view of the above circumstances, the present invention, when mixed with a resin material to form a composite material, reduces the shrinkage rate and mechanical strength anisotropy of the composite material as much as possible and has high mechanical strength. It is an object to provide a glass fiber that can realize the above.

  The glass fiber according to the present invention created to solve the above problems is a modified cross-section glass fiber having a flat cross-sectional shape perpendicular to the spinning direction, the cross-sectional shape of the cross-sectional shape of the glass fiber It has an asymmetry with respect to the longest dimension axis passing through the center of gravity.

  According to such a configuration, since the cross-sectional shape of the glass fiber has asymmetry with respect to the longest dimension axis passing through the center of gravity of the cross-section, the center of gravity of the cross-section is caused by the asymmetry. It will be unevenly distributed in the shortest dimension axis direction orthogonal to the longest dimension axis. Therefore, when the resin material is filled to form a composite material such as FRP and FRTP, the flow direction of the glass fiber is likely to be irregular, and the degree of orientation of the glass fiber after being filled in the resin material is increased. It can be adjusted to be lower. Therefore, the strength anisotropy of the molded composite material can be relaxed, and a composite material having more isotropic strength can be configured. In addition, when the cross-sectional shape forming a flat shape is based on the position of the center of gravity when the cross-sectional shape has symmetry with respect to the longest dimension axis of the cross-section, the position of the center of gravity is determined from the base point by the asymmetry of the cross-sectional shape. The larger the size (shift amount) that moves in the shortest dimension axis direction is, the more difficult it is to orient the glass fibers filled in the resin material.

  Said structure WHEREIN: It is preferable that the 1 or more protrusion part is formed in the outline of the said cross-sectional shape.

  In this way, when mixed with the resin material, in addition to the chemical bonding at the interface between the glass fiber and the resin material, the glass fiber protrusion is mechanically bonded so as to mesh with the resin material. become. Therefore, since the bonding force between the glass fiber and the resin material is increased by the synergistic effect of the chemical bond and the mechanical bond, the reinforcing effect in the longest dimension axis direction of the cross section of the glass fiber is increased, and the composite material machine It is possible to improve the mechanical strength, and at the same time, by adjusting the degree of orientation of the glass fibers to be low, it is possible to further relax the strength anisotropy and to form a composite material that is more isotropic in strength. That is, in the case where the protrusion is accompanied by a cross-sectional shape perpendicular to the spinning direction, the reinforcing structure is provided even in a direction in which the strength decreases after being combined and consolidated.

  Said structure WHEREIN: It is preferable that the flatness ratio of the said cross-sectional shape exists in the range of 1.5-10.0.

  That is, when the cross-sectional shape has a flatness ratio of less than 1.5, it is not preferable because an anisotropy improving effect with a sufficient shrinkage rate may not be realized when used in a composite material. Moreover, when the flatness ratio of a cross-sectional shape exceeds 10.0, manufacturing conditions etc. will become severe and management of the external shape glass fiber external shape shape | molded may become difficult, and it is unpreferable.

  Therefore, if the flatness ratio is within the above numerical range, it becomes possible to achieve high shape stability when a composite material is formed by mixing with a resin material, and glass having various cross-sectional shape dimensions depending on the application. It is preferable because fibers can be obtained. And from a viewpoint of enjoying such an effect, it is more preferable that the aspect ratio of the cross-sectional shape is in the range of 2.1 or more and 9.0 or less, and 2.3 or more and 8.0 or less. More preferably, it is within the range, more preferably within the range of 2.5 or more and 7.0 or less, and most preferably within the range of 2.7 or more and 6.0 or less.

  Said structure WHEREIN: It is preferable that the circle equivalent diameter of the said cross-sectional shape exists in the range of 5 micrometers or more and 30 micrometers or less. Here, the equivalent circle diameter means the diameter of a circle having the same cross-sectional area of the glass fiber. For the calculation of the equivalent circle diameter, for example, a method of photographing and analyzing the cross section of the glass fiber perpendicular to the spinning direction is used to derive the diameter of a circle corresponding to a perfect circle having the same area. Good.

  That is, when the equivalent circle diameter of the cross-sectional shape is less than 5 μm, it is difficult to maintain a stable shape, and the production cost for realizing it increases, which is not realistic. On the other hand, when the equivalent circle diameter of the cross-sectional shape exceeds 30 μm, it may be difficult to rapidly cool the glass fiber, and in this case, the problem that the intended cross-sectional shape is difficult to be realized occurs.

  In this way, since it can be applied to various composite materials used for various purposes, the product dimensions of various composite materials can be adjusted more precisely than before. In addition, from the viewpoint of enjoying such effects, the equivalent circular diameter of the cross-sectional shape is more preferably in the range of 6 μm to 24 μm, and further preferably in the range of 9 μm to 18 μm. preferable.

  In addition, the glass fiber manufacturing method according to the present invention, which was created to solve the above problems, includes a flat nozzle hole and a nozzle having a protruding portion protruding in the spinning direction at a part of the tip portion. By drawing the molten glass downward, a modified cross-section glass fiber having the above-described configuration is formed.

  According to such a method, in a state where a part of the molten glass is held by the protruding portion of the nozzle, the molten glass facing the side where the protruding portion of the nozzle is not formed is released to the outside air and cooled early. Can do. In other words, the glass fiber having the above-mentioned shape can be formed with high molding accuracy because it is possible to increase the cooling efficiency of the portion where the molten glass is desired to be cooled at an early stage while regulating the substantial shape change of the molten glass by the protruding portion of the nozzle. Can be manufactured. In addition, when obtaining a flat cross-sectional shape with flatness, restrictions such as cooling conditions and drawing speed are reduced, so that the allowable range of spinning conditions such as temperature and drawing speed can be made wider, and stable molding conditions Can be adopted, and it becomes easy to perform the molding management of the glass fiber.

  In addition, as a nozzle used with said manufacturing method, the thing provided with the following structures is preferable, for example. That is, the nozzle includes the longest dimension axis of the nozzle hole passing through the center of gravity of the flat nozzle hole and is parallel to the spinning direction of the molten glass. As such, it is preferable that the length in the vertical direction from the nozzle tip is asymmetric. If such a nozzle is used, the surface of the molten glass drawn from the nozzle can be partially and strongly cooled so that the cross-sectional shape of the cooled and solidified glass fiber has the above asymmetry. It becomes.

  Specific examples of such nozzle shapes include the following. For example, in the cross section perpendicular to the spinning direction of the molten glass, only one wall surface of the portion along the longitudinal direction of the nozzle hole long in one direction has a shape protruding in the spinning direction, or spinning. By having an uneven shape in the direction, a part of the tip of the nozzle is relatively recessed and has an asymmetric outer shape.

  Such asymmetry in the spinning direction dimension of the outer shape of the nozzle is important to ensure the flatness of the glass fiber to be molded, but the longitudinal cross-sectional shape parallel to the spinning direction of the nozzle opening is not symmetrical. Making the shape extremely different on both sides of the comparison surface (for example, the above-mentioned reference plane) may shorten the useful life of the nozzle, making it difficult to manufacture the nozzle, and is economical even if it can be realized. However, it is not preferable because it becomes expensive equipment. From such a viewpoint, for example, when a nozzle having a shape in which only one wall surface in the longitudinal direction of the nozzle hole protrudes in a cross section perpendicular to the spinning direction of the molten glass, the length of the protruding portion is Should not be longer than 5 times the length of the short side.

  Further, the glass fiber manufacturing method of the present invention is an irregular shape with little dimensional variation and shape variation depending on molding conditions if the asymmetric nozzle hole is formed into an asymmetric shape by forming grooves. It becomes easy to obtain glass fibers having a cross-sectional shape.

  The groove formed in the nozzle hole may appropriately adopt an arc shape, V shape, U shape, or concave shape.

  In the glass fiber manufacturing method of the present invention, the fixed point observation of the specific shape of the nozzle shape and the shape of the glass to be formed can be managed by a sensor or the like, and the nozzle temperature, spinning speed, etc. can be finely adjusted by reflecting the result. If it comprises, it will lead to obtaining a more stable shaping | molding shape, and it is still more preferable when performing stable production.

  Since the cross-sectional shape of the modified cross-section glass fiber according to the present invention as described above has an asymmetry in the cross-sectional shape with respect to the longest dimension axis passing through the center of gravity of the cross-section, the composite material is constituted with various resin materials. In addition, anisotropy of the shrinkage rate of the composite material is not observed, and it has high mechanical strength, and isotropic strength can be realized.

  Further, the method for producing a modified cross-section glass fiber according to the present invention has a flat nozzle hole and draws the molten glass downward from a nozzle having a protruding portion protruding in the spinning direction at a part of the tip portion. Since the modified cross-section glass fiber of the present invention is formed, it is possible to obtain a glass fiber having a precise cross-sectional dimension while improving the cooling efficiency.

It is a cross-sectional view which shows notionally the cross-sectional shape of the irregular cross-section glass fiber which concerns on Example 1 of this invention. It is explanatory drawing regarding the manufacturing equipment of the irregular cross-section glass fiber shown in FIG. 1, (A) is a partial whole view, (B) is an expanded longitudinal cross-sectional view of the X section of (A), (C) is Y of (B). -Y represents a cross-sectional view. It is a cross-sectional view which shows notionally the cross-sectional shape of the irregular cross-section glass fiber which concerns on Example 2 of this invention. It is a photograph of the cross-sectional shape of the manufactured irregular cross-section glass fiber. It is a photograph of the cross-sectional shape of the other irregular cross-section glass fiber manufactured. It is a cross-sectional view which shows notionally the cross-sectional shape of the irregular cross-section glass fiber which concerns on Example 3 of this invention. It is explanatory drawing regarding the manufacturing equipment of the other irregular cross-section glass fiber shown in FIG. 6, (A) is a partial whole view, (B) is an expanded longitudinal cross-sectional view of the X section of (A), (C) is (B). YY sectional drawing of this is represented. It is a photograph of the cross-sectional shape of the other irregular cross-section glass fiber manufactured.

  Embodiments according to the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a cross-sectional view of a modified cross-section glass fiber according to Example 1 of the present invention. The glass fiber 10 is used, for example, as a structural material for electronic components, and the external features thereof are as follows.

  That is, the external feature of the glass fiber 10 is that when the glass fiber 10 is divided into two with the longest dimension axis L passing through the center of gravity P of the cross section perpendicular to the spinning direction as a boundary, the glass fiber 10 is divided by the longest dimension axis L. The contour portion 11a on one side and the contour portion 11b on the other side of the contour of the glass fiber 10 to be formed have an asymmetry with respect to the longest dimension axis L. Specifically, this asymmetry is caused by the curvature radius R1 of the corner portion of the contour portion 11a on one side being different from the curvature radius R2 of the corner portion of the contour portion 11b on the other side. In this way, when the composite material is configured with various resin materials using such glass fibers 10 due to the asymmetry of the cross-sectional shape with respect to the longest dimension axis L passing through the center of gravity P of the cross section, Anisotropy of the shrinkage rate of the material is not recognized, and it has high mechanical strength, and isotropic strength can be realized. Of course, such a cross-sectional asymmetry is a form obtained intentionally. That is, the glass fiber 10 having this cross-sectional shape is not temporarily formed due to unintended fluctuations in manufacturing conditions, and is not caused by the action of unintended bubbles or foreign matters mixed in the glass fiber 10. It also does not indicate a diameter asymmetry. In other words, it is a shape that is continuously obtained in a state in which the production conditions relating to spinning are fixed without causing these production defects.

  Further, another external feature of the glass fiber 10 is that when the glass fiber 10 is divided into two with the shortest dimension axis S passing through the center of gravity P as a boundary, the outline of the glass fiber 10 divided by the shortest dimension axis S. The one-side contour portion 11c and the other-side contour portion 11d are symmetric with respect to the shortest dimension axis S. In this way, in addition to realizing the strength isotropy of the composite material molded as FRP or the like, it is possible to obtain an appropriate filling property of the resin material, and the glass fiber 10 and the resin material are familiar with each other. Since it becomes easy, the defect resulting from the surface of the glass fiber 10 becomes difficult to generate | occur | produce.

  Further, this glass fiber 10 has a longest dimension A passing through the center of gravity P of its cross section of 33.3 μm, and a distance B between two parallel straight lines parallel to this and contacting the contour 11 of the cross section is 9.4 μm. It is. Therefore, the cross-sectional shape has a flatness ratio of 3.54, which is a value obtained by dividing the longest dimension A passing through the center of gravity P by the distance B between two parallel straight lines parallel to the cross-sectional contour and in contact with the contour of the cross-section. Is in the range of 1.5 to 10.0.

  The flatness ratio is measured, for example, by polishing the glass fiber 10 embedded in a resin material or the like, exposing a cross section perpendicular to the spinning direction of the glass fiber 10, and using a stereomicroscope or an electron microscope. The longest dimension A that passes through the center of gravity of the cross section of the glass fiber recognized on the polished surface and the distance B between two parallel lines that are parallel to this and touch the contour of the cross section are measured, and A / B is calculated. By doing. Specifically, image analysis may be performed using an image obtained by a stereomicroscope or an electron microscope to derive the center of gravity position and the flatness ratio.

  Further, the glass fiber 10 has an equivalent circle diameter of 18.1 μm and falls within a range of 5 μm to 30 μm.

  Next, the manufacturing procedure of the glass fiber 10 comprised as mentioned above is demonstrated based on FIG. 2 (A)-(C).

  First, as shown in FIG. 2 (A), a molten glass G made of E glass obtained by melting various glass raw materials so as to be in a high temperature state is subjected to a mixing and homogenization operation such as stirring to obtain a homogeneous state. After that, the heat-resistant bushing 20 made of platinum alloy is supplied. Next, the glass fiber 10 is manufactured by cooling and solidifying the molten glass G while pulling the molten glass G downward from a plurality of platinum alloy heat-resistant nozzles 21 attached to the bottom of the bushing 20. In addition, the manufactured glass fiber 10 is wound up on the paper tube with which the winding apparatus 30 arrange | positioned below is mounted | worn.

  And in the above-mentioned manufacturing procedure, the nozzle 21 used has the protrusion part 21a which protruded below in a part of front-end | tip part, as shown to FIG. 2 (B). Therefore, the region excluding the protruding portion 21a at the tip of the nozzle 21 is a notch 21b. Further, as shown in FIG. 2C, the nozzle hole 22 of the nozzle 21 has a flat shape (oval shape) having a long axis (longest dimension axis) T passing through the center of gravity P1 of the cross section. In this embodiment, the protrusion 21 a formed at the tip of the nozzle 21 is formed over the half circumference of the nozzle hole 22 with the major axis T of the nozzle hole 22 as a boundary.

  When the molten glass G is spun from the nozzle 21 configured in this manner, the surface on one side of the molten glass G facing the protruding portion 21a of the nozzle 21 flows down while being guided along the protruding portion 21a. The other surface of the molten glass G facing the notch 21b of the nozzle 21 is rapidly cooled through the notch 21b. Therefore, it is possible to cool the molten glass G spun from the nozzle hole 22 while suppressing the cross-sectional outline from being rounded by the surface tension, so that the glass fiber 10 having a flat cross-sectional shape can be reliably secured. Can be manufactured.

  Here, the process until the molten glass G flows out and cools will be described in detail. The surface on one side of the molten glass G facing the protruding portion 21a of the heat resistant nozzle 21 is a non-free surface in contact with the protruding portion 21a. In addition, it is stretched downward while being guided by the protruding portion 21a of the heat-resistant nozzle 21, and the temperature is lowered and cooled in the process. Therefore, the contour part 11b which shows a comparatively small curvature and has a linear part among the outlines of the glass fiber 10 shown in FIG. 1 is formed by the surface of the one side of the molten glass G which faces the protrusion part 21a. The On the other hand, the surface on the other side of the molten glass G facing the notch portion 21b of the heat-resistant nozzle 21 is a free surface, and the surface is opened to the atmosphere before the protruding portion 21a side through the notch portion 21b. Try to round due to tension. Therefore, the one side contour portion 11a having a larger curvature than the contour portion 11b is formed by the surface on the other side of the molten glass G facing the notch portion 21b.

  As shown in FIG. 2 (B), the shape of the nozzle 21 is based on a plane U including the major axis T of the nozzle hole 22 and parallel to the spinning direction of the molten glass G. On the other hand, it has asymmetry. Further, as shown in FIG. 2C, the nozzle 21 has a shape in which the planar shape of the contour has mirror symmetry with respect to the long axis T passing through the center of gravity P1.

  FIG. 3 is a cross-sectional view of a modified cross-section glass fiber according to Example 2 of the present invention. The glass fiber 10 according to the second embodiment is different from the glass fiber 10 according to the first embodiment in that one or more (two in the illustrated example) projecting portions 12 project outward from the contour 11 having a cross-sectional shape. Is the point that is formed. In this way, when mixed with the resin material, in addition to chemical bonding at the interface between the glass fiber 10 and the resin material, mechanically so that the protrusions 12 of the glass fiber 10 mesh with the resin material. Will be combined. Therefore, since the bonding force between the glass fiber 10 and the resin material is increased, the reinforcing effect of the resin material by the glass fiber 10 can be enhanced, and the mechanical strength of the composite material can be further improved. The protrusion 12 has a maximum height of 1/5 or less of the longest dimension A passing through the center of gravity P of the cross section when the line connecting the two protrusion start points on the contour line of the cross section is the base. Preferably there is. Furthermore, when the protrusion 12 has a line segment connecting two protrusion start points as the base, the length of the transverse line of the protrusion 12 that is parallel to the base and half of the maximum height is It is preferably 1/5 or less of the longest dimension A passing through the center of gravity P of the cross section.

  Such a protrusion 12 can be formed by changing and adjusting the spinning speed and the bushing temperature when the glass fiber 10 is manufactured according to the method for manufacturing the glass fiber 10 described in the first embodiment. That is, by changing the spinning speed or the like, glass fibers having different cross-sectional sizes and different cross-sectional outline shapes can be intentionally obtained.

  Specifically, in Example 1, the viscosity of the molten glass G is sufficiently high, and the shape of the nozzle hole 22 is substantially maintained during the spinning process, and no protrusion is observed on the glass fiber 10, but in Example 2, The viscosity of the molten glass G is relatively low. Therefore, in the spinning process, the end side of the soft molten glass G wraps around the protruding portion 21a side of the nozzle 21 without maintaining the shape of the nozzle hole 22. As a result, the protrusion 12 is formed on the glass fiber 10 obtained by cooling and solidifying the molten glass G.

  And as an example of the manufacturing conditions of the glass fiber 10 in which the projection part 12 was formed in this way, spinning speed shall be 600 m / min and bushing temperature shall be 1100 degreeC. Under this condition, when the glass fiber 10 is manufactured, the contour radius of the contour portion 11a and the contour portion 11b which are different in the radius of curvature R1 and the radius of curvature R2 and are separated by the longest dimension axis L in the contour of the cross section. Among these, it has been confirmed that protrusions 12 protruding by about 1 μm appear at both end portions of the contour portion 11b formed on the protruding portion 21a side of the nozzle. A cross-sectional photograph of the glass fiber 10 actually obtained under the above spinning conditions is shown in FIG. In the figure, the portion displayed in white indicates the glass fiber 10. The image shown in the figure is a photograph of the polished surface taken under a stereomicroscope after mirror-polishing the resin in which the glass fiber 10 is embedded.

  As for the glass fiber 10 having a cross-sectional shape in which the protrusions 12 appear in two places as shown in FIG. 3, the longest dimension A passing through the center of gravity P of the cross section is 43.5 μm, and the protrusion of the cross section parallel to this is shown. A distance B between two parallel lines in contact with the contour 11 excluding the portion 12 is 10.2 μm. Therefore, the flatness ratio obtained by dividing the longest dimension A passing through the center of gravity P by the distance B between two parallel lines parallel to this and excluding the protrusion 12 on the cross section is 4.3. It is in the range of 5 or more and 10.0 or less. Moreover, the circle equivalent diameter of this glass fiber 10 is 23.3 micrometers, and exists in the range of 5 micrometers or more and 30 micrometers or less.

  Moreover, although not shown in figure, the glass fiber 10 which concerns on Example 2 from which external dimensions etc. differ can be obtained by employ | adopting other conditions. For example, when the spinning speed is 400 m / min and the bushing temperature is 1100 ° C., the following glass fiber 10 can be obtained. That is, the glass fiber 10 has a longest dimension A passing through the center of gravity P of the cross section of 53.4 μm, and a distance B between two parallel lines parallel to this and excluding the protrusion 12 of the cross section is in contact with the outline. 13.5 μm. Therefore, the flatness ratio (A / B) is 4.0, which is a value in the range of 1.5 to 10.0. The equivalent circle diameter is 28.9 μm, which is a value in the range of 5 μm to 30 μm. Further, the cross section of the glass fiber 10 has a flat cross section as described above, and the cross section has an asymmetry with respect to the longest dimension axis L passing through the center of gravity P of the cross section. And the cross-sectional shape has symmetry with respect to the shortest dimension axis S passing through the center of gravity P of the cross-section. Moreover, it has two projection parts 12 in the outline of a cross-sectional shape.

  Further, the glass fiber 10 according to the second embodiment having a smaller outer dimension and a larger flatness includes the following. That is, by setting the spinning speed to 1500 m / min and the bushing temperature to 1100 ° C., the longest dimension A passing through the center of gravity P of the cross section is 34.3 μm, and the contour excluding the protrusion 12 on the cross section parallel to this. The distance B between two parallel lines in contact with each other is 6.0 μm, the flatness ratio (A / B) is 5.7 and is in the range of 1.5 to 10.0, and the equivalent circle diameter It was also confirmed that another modified cross-section glass fiber 10 having a thickness of 15 μm and a range of 5 μm to 30 μm was obtained. A cross-sectional photograph of the obtained glass fiber 10 is shown in FIG. Since the modified cross-section glass fiber 10 has a small equivalent circle diameter and high flatness, the effect of improving the anisotropy of the shrinkage rate is further increased.

  FIG. 6 is a cross-sectional view of a modified cross-section glass fiber according to Example 3 of the present invention. The glass fiber 10 according to Example 3 is obtained by spinning molten glass G in the same manner as in Example 1 or Example 2. In the glass fiber 10 according to the third embodiment, one protrusion 13 protruding outward is formed at a substantially central position in the longest dimension axis direction of the glass fiber 10 on a cross-sectional outline 11. Also in Example 3, as in Example 2, when compounded with the resin material, the protrusion 13 of the glass fiber 10 is mechanically coupled so as to mesh with the resin material, so that the mechanical strength is improved. It will lead to Here, the maximum height when the line segment connecting the two protrusion start points on the outline of the cross-sectional shape of the protrusion 13 is the base is 1/5 or less of the longest dimension A passing through the center of gravity P of the cross-section. .

  In addition, the deformed cross-section glass fiber 10 has a longest dimension A passing through the center of gravity P of its cross section of 34.6 μm, and a distance between two parallel lines that are parallel to this and excluding the projecting portion 12 of the cross section. B is 5.5 μm, the aspect ratio (A / B) is 6.3 and is in the range of 1.5 to 10.0, and the equivalent circle diameter is 15.6 μm to 5 μm to 30 μm. Is in range.

  The glass fiber 10 which concerns on Example 3 of this invention is with respect to the long axis T of the cross section of the nozzle internal diameter which passes along the gravity center P1 of the cross section of the nozzle hole 22, as shown to FIG. 7 (A)-(C). The nozzle hole 22 having asymmetry is provided. That is, as shown in FIGS. 7B and 7C, the nozzle hole 22 has a shape in which the planar shape of the outline does not have mirror symmetry with respect to the long axis T passing through the center of gravity P1. Thus, a semicircular arc-shaped groove 23 is formed. The molten glass G flowing out from the groove 23 forms the projection 13 of the glass fiber 10 shown in FIG.

  7B and 7C, one arcuate groove 23 is formed on a plane perpendicular to the spinning direction of the nozzle 21, but the groove 23 has a shape other than the arcuate shape. Further, it may be V-shaped, U-shaped, concave or the like. In this example, the number of grooves is one, but a larger number of grooves such as two or three may be provided.

  Alternatively, the semicircular groove 23 formed in the nozzle hole 22 may be formed by shifting from the central position of the nozzle hole 22 to one side in the major axis direction of the nozzle hole 22. If it does in this way, the position of the projection part 13 formed in the glass fiber 10 can be shifted from a center position.

  Further, the glass fiber 10 in which the protrusion 13 is thus formed by the groove 23 also reflects the difference in shape between the glass fiber 10 according to Example 1 and the glass fiber 10 according to Example 2 described above. It can be made into the shape made. That is, if the viscosity of the molten glass G is adjusted relatively low by adjusting the viscosity of the molten glass G drawn from the nozzle 21, the two projections 12 as in the second embodiment are formed. Can do. Conversely, when the viscosity of the molten glass G is relatively increased, the shape in which the two protrusions 12 are not formed can be obtained.

  FIG. 8 is a photograph of a cross section perpendicular to the spinning direction of the glass fiber 10 obtained when the viscosity of the molten glass G is lowered. Here, three protrusions 12 and 13 are formed, and the central protrusion 13 obtained by the groove 23 is formed at a biased position. Moreover, the two protrusions 12 formed at both ends are formed by the soft molten glass G wrapping around.

  According to the modified cross-section glass fibers 10 according to Examples 1 to 3 of the present invention as described above, various resins are caused by the asymmetry of the cross-sectional shape with respect to the longest dimension axis L passing through the center of gravity P of the cross-section. When a composite material is formed together with a material, there is no anisotropy of the shrinkage rate of the molded body of the composite material, and it has a high mechanical strength and can realize the isotropy of the strength. it can. That is, since the magnitude (shift amount) by which the center of gravity moves from the center of gravity of the flat shape having symmetry, that is, the geometric center, due to the asymmetry of the cross-sectional shape, the glass fiber 10 is made of organic resin. When used together with a material, when dispersed in a liquid organic resin material, the structure does not show orientation along the flow of the resin material, and the structure is such that the strength and the anisotropy of shrinkage are alleviated. In addition, in the case where the protrusions 12 and 13 are accompanied by a cross-sectional shape perpendicular to the spinning direction, the structure is provided with reinforcement in a direction in which the strength decreases after being combined and consolidated.

  In addition, this invention is not limited to the said Example, It can implement in a various form. For example, a predetermined amount of various types of sizing agents may be applied to the fiber surface of the modified cross-section glass fiber 10 by various methods depending on the application.

  In addition, the glass fiber 10 according to the above embodiment can be used as a cake or cheese by bundling a plurality of bundles as a glass strand after applying a sizing agent by using an applicator and winding it around the surface of a cylindrical paper tube. Well, it may be stored in this state, and further subjected to various processing such as cutting, drying, combining yarn, twisting yarn, dispersion, weaving, glass chopped strand, glass roving, yarn or mat, glass paper, glass cloth, etc. Various glass fiber products may be obtained.

  Furthermore, the glass fiber 10 which concerns on said Example may extend the use as needed to the use where other glass fibers are used, such as not only FRP but the reinforcement use of concrete. In addition to this, it is used as an optical member that is molded into various display substrates etc. in combination with a transparent resin material using a glass composition having a desired transmittance and refractive index in consideration of optical performance, It can be used for various purposes such as heat-resistant shielding materials and laminated materials, and can also be applied to lightweight materials such as hollow glass fibers.

  In Examples 2 and 3, the shape of the protrusions 12 and 13 of the glass fiber 10 is exemplified by a gentle parabolic protrusion. However, for example, it may be an acute angular protrusion. . Further, the protrusions 12 and 13 may be multiple protrusions such that there is a protrusion in the middle of the protrusion.

  Further, in the above embodiment, as the nozzle 21 used for manufacturing the glass fiber 10, the protrusion 21 a is provided at a part of the tip of the nozzle 21, and the shape of the nozzle 21 includes the long axis T of the nozzle hole 22. And although what has asymmetry with respect to the plane U parallel to the spinning direction of the molten glass G was demonstrated, you may have symmetry with respect to this plane U.

  In other words, even when the same nozzle 21 is used, various adjustments can be made to various manufacturing conditions such as the temperature of the molten glass G, the flow rate of the molten glass G, the cooling rate of the molten glass G, etc. Glass fiber 10 having asymmetry can be produced. Therefore, even when glass fibers having different cross-sectional shapes are manufactured, the intended shape can be easily formed without replacing the nozzle 21 as much as possible. Therefore, even when producing glass fibers 10 having different cross-sectional shapes, the loss of molding time of the glass fibers 10 during production caused by the replacement of the nozzles 21 can be minimized and stable. Operation becomes possible.

DESCRIPTION OF SYMBOLS 10 Profile cross-section glass fiber 11 Cross-sectional outline 11a Contour part 11b of the outline with respect to the longest dimension axis Contour part 11c of the outline with respect to the longest dimension axis 11c Contour part 11d of the outline with respect to the shortest dimension axis Shortest dimension axis Contour portions 12 and 13 on the other side of the contour Protrusion portion 20 Bushing 21 Heat resistant nozzle 21a Protruding portion 21b Notch portion 22 Nozzle hole 23 Groove 30 Winding device G Molten glass

Claims (5)

A modified cross-section glass fiber having a flat cross-sectional shape perpendicular to the spinning direction,
The cross-sectional shape is, have a asymmetric with respect to the longest dimension axis passing through the center of gravity of the cross section,
Having a protrusion on only one side of the partial outline of the cross-sectional shape divided into two by the longest dimension axis, and the protrusions are respectively formed at both ends in the longest dimension axis direction;
Among the partial contours on the one side, the non-projection portions formed between the projection portions are substantially linear, and the formation region of the non-projection portions is the longest than the formation region of the projection portions. Wide in the dimension axis direction,
An irregular cross-section glass fiber , wherein a flatness ratio of the cross-sectional shape is 1.5 or more and 10.0 or less, and a circle-equivalent diameter of the cross-sectional shape is 5 to 30 μm . 2. The modified cross-section glass fiber according to claim 1, wherein in the partial contour on the one side, a protrusion is further formed at an intermediate portion in the longest dimension axis direction of the non-projecting portion. A modified cross-section glass fiber having a flat cross-sectional shape perpendicular to the spinning direction,
The cross-sectional shape is asymmetric with respect to the longest dimension axis passing through the center of gravity of the cross-section;
A protrusion is formed in the middle of the longest dimension axis direction only on one side of the partial contour of the cross-sectional shape divided into two by the longest dimension axis,
Of the partial contour on the one side, the non-projection portions formed on both sides of the projection portion are substantially linear, and the non-projection portion formation region is longer than the projection portion formation region. Wide in the dimension axis direction,
An irregular cross-section glass fiber, wherein a flatness ratio of the cross-sectional shape is 1.5 or more and 10.0 or less, and a circle-equivalent diameter of the cross-sectional shape is 5 to 30 μm. The protrusion has a longest dimension that passes through the center of gravity of the cross section when the line connecting the two protrusion start points on the partial contour on the one side is the base and the maximum height with respect to the base is the reference. The modified cross-section glass fiber according to any one of claims 1 to 3, wherein the glass fiber is 1/5 or less. The protrusion is parallel to the base and half the maximum height based on the base when the line connecting the two protrusion start points on the partial contour on the one side is the base. The length of the transverse line segment of the protrusion part located is 1/5 or less of the longest dimension which passes the gravity center of the said cross section, The irregular cross-section glass of any one of Claims 1-4 characterized by the above-mentioned. fiber.