Method for producing glass fiber direct yarn

Abstract

The present invention aims to improve the unwinding property of glass fiber direct yarn at the end surface. The method for producing glass fiber direct yarn comprises a winding process of winding glass raw yarn into a cylindrical shape while hanging it obliquely. In the winding process, the regression number of the oblique hanging is 10 or more, the regression number is set as "A", and the maximum integer less than 1 / 2 of the regression number is set as "(A / 2) * ", set the largest integer less than 1 / 4 of the regression number to "(A / 4) * When the number of oblique winding cycles is expressed as a fraction "a+(b / A)", the smaller value between "b" and "A-b" is the spacing parameter "(A / 2) * ‑(A / 4) * " and above and "(A / 2) * The glass strands are wound while being hung obliquely under the condition of less than ‑1”.

Description

Technical Field

[0001] The invention relates to a method for producing glass fiber direct yarn. Background Art

[0002] As disclosed in Patent Document 1, glass fiber direct yarn (DWR: Direct Wound Roving) produced by a direct winding method is used as a reinforcing fiber for a composite material composed of a combination of a resin and a reinforcing material in molding methods such as pultrusion molding and filament winding.

[0003] Glass fiber direct yarn is typically produced as follows. First, molten glass is drawn from a platinum bushing equipped with hundreds to thousands of nozzles into glass filaments measuring several to twenty microns in diameter. A sizing agent is then applied to the surface of each filament, and hundreds to thousands of these filaments are aligned to form a glass strand. This strand is then wound into a cylindrical shape while being hung diagonally on a rotating collet.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent No. 4110923 Summary of the Invention

[0007] Problems to be solved by the invention

[0008] In conventional glass fiber direct yarns, when the glass strands are unwound and drawn out, the glass strands may get caught at the turning points of the glass strands at the end surfaces.

[0009] An object of the present invention is to improve the unwinding property of glass fiber direct yarn at the end surface.

[0010] Means for solving problems

[0011] The method for producing a glass fiber direct yarn for solving the above-mentioned problem comprises a winding step of winding a glass fiber strand into a cylindrical shape while hanging it obliquely. In the winding step, the regression number of the oblique hanging is 10 or more, the regression number is denoted as "A", and the largest integer less than 1 / 2 of the regression number is denoted as "(A / 2) * ", set the largest integer less than 1 / 4 of the above regression number as "(A / 4) * When the number of oblique loop windings is expressed as a fraction "a+(b / A)", the smaller value between "b" and "Ab" is the interval parameter "(A / 2) * -(A / 4) * " and above and "(A / 2) * Under the condition of -1" or less, the glass strands are wound while being hung obliquely.

[0012] According to the above configuration, the distance between the turning points of the glass strands at the end face of the glass fiber direct yarn is increased. As a result, when the glass fiber direct yarn is unwound and the glass strands are drawn out, interference between the turning points of the glass strands can be suppressed, thereby improving the unwoundness of the glass fiber direct yarn at the end face.

[0013] In the above-mentioned method for producing the glass fiber direct yarn, it is preferred that the above-mentioned interval parameter is "(A / 2) * -1" condition, the glass strands were wound while being hung obliquely.

[0014] According to the above configuration, the effect of improving the unwinding property of the glass fiber direct yarn at the end surface can be more significantly obtained.

[0015] Effects of the Invention

[0016] According to the present invention, the unwinding property of the glass fiber direct yarn at the end surface can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a three-dimensional diagram of glass fiber direct yarn.

[0018] Figure 2 This is a diagram illustrating the winding process.

[0019] Figure 3 It is an explanatory diagram showing the displacement of the circumferential position of the turning point due to one reciprocating movement.

[0020] Figure 4 It is an explanatory diagram showing the displacement of the circumferential position of the turning point per reciprocating movement.

[0021] Figure 5 It is an explanatory diagram showing the displacement of the circumferential position of the turning point per reciprocating movement in the first example.

[0022] Figure 6 It is an explanatory diagram showing the displacement of the circumferential position of the turning point per reciprocating movement in the second example.

[0023] Figure 7 It is an explanatory diagram showing the displacement of the circumferential position of the turning point per reciprocating movement in the third example. DETAILED DESCRIPTION

[0024] An embodiment of the present invention will be described below.

[0025] like Figure 1 As shown, the glass fiber direct yarn 10 is formed into a cylindrical shape by winding glass strands GS. The winding shape of the glass fiber direct yarn 10 is, for example, a square-end cheese shape (cylindrical shape). In addition, the axial length of the glass fiber direct yarn 10 is described as the winding width H.

[0026] The method for producing the glass fiber direct yarn 10 includes a spinning step of obtaining a glass strand GS from molten glass and a winding step of winding the glass strand GS.

[0027] The spinning process employs a known method of spinning molten glass using a bushing. For example, molten glass drawn from a bushing equipped with multiple nozzles is drawn into glass filaments. Subsequently, a sizing agent is applied to the surface of each glass filament, and then hundreds to thousands of glass filaments are aligned to form glass strands (GS).

[0028] The diameter of the glass strand GS is, for example, 1 mm or more and 10 mm or less. The glass strand GS is composed of, for example, 100 to 10,000 glass filaments. The diameter of the glass filaments forming the glass strand GS is, for example, 3 μm or more and 30 μm or less.

[0029] Examples of glass include E glass (glass with an alkali content of 2% or less), D glass (low dielectric constant glass), AR glass (alkali-resistant glass), C glass (acid-resistant glass), M glass (high elastic modulus glass), S glass (high strength, high elastic modulus glass), T glass (high strength, high elastic modulus glass), H glass (high dielectric constant glass), and NE glass (low dielectric constant glass). For example, the composition of E glass, in terms of mass % based on oxides, is preferably SiO2: 52-62%, Al2O3: 10-16%, B2O3: 0-8%, MgO: 0-5%, CaO: 16-25%, and RO (where R is at least one of Li, Na, and K): 0-2%.

[0030] Examples of the coating component (resin component) in the sizing agent include urethane resins, epoxy resins, vinyl acetate resins, etc. The sizing agent may contain a lubricant, a silane coupling agent, etc. as needed.

[0031] like Figure 2 As shown, in the winding process, a traverse 12 is used to wind the glass strand GS while obliquely hanging it relative to a rotating cylindrical collet 11, thereby producing a glass fiber direct yarn 10. As the traverse 12, a well-known traverse such as a steel traverse or a traverse using a cam mechanism that converts the rotational force of a motor into reciprocating linear motion can be used.

[0032] In the winding process, the oblique hanging is performed so as to form the return number and the loop winding number that satisfy the following first and second conditions. First, the return number and the loop winding number of the oblique hanging will be described.

[0033] The regression number is a value representing the number of times the glass strand GS moves around the winding axis X until it returns to the same position in the circumferential direction, taking the one-way movement of the glass strand GS in the axial direction of the winding axis X, that is, the movement of the glass fiber direct yarn 10 according to the winding width H as 1 unit.

[0034] For example, when the regression number is "10," the glass strand GS returns to the same circumferential position around the winding axis X by repeating 10 single-pass movements of the glass strand GS in the axial direction, that is, by repeating 5 reciprocating movements. When the regression number is an even number, the glass strand GS returns to the same circumferential position around the winding axis X at the same axial position, that is, on the same plane perpendicular to the winding axis X. When the regression number is an odd number, the glass strand GS returns to the same circumferential position around the winding axis X at the axial position of the single-pass movement in the axial direction.

[0035] On the same plane perpendicular to the winding axis X and including the end faces of the glass fiber direct yarn 10, the glass strands GS are located at any of a number of circumferential positions equal to the number of regressions arranged at equal intervals around the winding axis X. These positions gradually move radially outward as winding progresses. The positions of the glass strands GS at both end faces of the glass fiber direct yarn 10 serve as turning points for the glass strands GS.

[0036] The number of loop windings is the number of windings of the glass strand GS during the reciprocating movement of the glass strand GS. In other words, it is a value twice the rotation speed of the collet 11 during the movement of the glass strand GS over the winding width H of the glass fiber direct yarn 10.

[0037] Alternatively, the number of loop windings can be calculated using the number of arrangement strips and the regression number. The number of arrangement strips is the number of times the glass strand GS rotates around the collet 11 from the start point of winding to the point at which the circumferential position of the glass strand GS first returns to the circumferential position of the start point. By dividing the number of arrangement strips by the regression number, the number of windings of the glass strand GS during a single pass of movement, or the single-pass winding number, is obtained. The loop winding number, which is double the single-pass winding number, is then calculated.

[0038] Next, the first and second conditions will be described.

[0039] The first condition is that the regression coefficient is greater than or equal to 10. The regression coefficient is preferably greater than or equal to 11 and less than or equal to 60, and more preferably greater than or equal to 13 and less than or equal to 30.

[0040] The second condition is that, when the regression number is "A" and the number of cyclic windings is expressed as a fraction "a+(b / A)", the smaller value of "b" and "Ab", that is, the interval parameter, is within a specific range R. The largest integer less than 1 / 2 of the regression number is "(A / 2)* ", set the largest integer less than 1 / 4 of the regression number to "(A / 4) * ", the above-mentioned specific range R is "(A / 2) * -(A / 4) * " and above and "(A / 2) * -1" range or less.

[0041] The largest integer less than 1 / 2 of the regression number is equal to the value obtained by rounding down the value of 1 / 2 of the regression number. The largest integer less than 1 / 4 of the regression number is equal to the value obtained by rounding down the value of 1 / 4 of the regression number. For example, when the regression number is "13", (A / 2) * = 6 (=13 / 2=6.5→6), (A / 4) * is 3 (=13 / 4=3.25→3).

[0042] Figure 3 and Figure 4 This is an explanatory diagram showing, by arrow Y, the displacement of the circumferential position P of the turning point of the glass strand GS at one end surface of the glass fiber direct yarn 10 per reciprocating movement. Figure 3 The displacement of the turning point based on one reciprocating movement is shown. Figure 4 The displacement of the turning point in each reciprocating movement until the turning point returns to the initial circumferential position P is shown.

[0043] like Figure 3 As shown, at the end face on one side of the glass fiber direct yarn 10, the number of circumferential positions P that the turning point of the glass strand GS can take is the same as the number of regression numbers, and each circumferential position P is arranged circumferentially according to the value obtained by dividing 360° by the regression number (i.e., the angle interval θ). Figure 3 and Figure 4 The figure shows a case where the regression number is 13. In this case, the number of circumferential positions P is 13, and the angular interval θ between the circumferential positions P is approximately 28° (≈360 / 13).

[0044] like Figure 3 As shown, when the number of cyclic windings is expressed as a fraction, the above-mentioned "b" and "Ab" are parameters representing the circumferential interval between the circumferential position P (P1) of the turning point before the reciprocating movement and the circumferential position P (P2) of the turning point after the reciprocating movement when the glass raw yarn GS is reciprocated once.

[0045] Specifically, the counterclockwise circumferential interval between the circumferential position P (P1) of the turning point before reciprocating movement and the circumferential position P (P2) of the turning point after reciprocating movement is calculated from an angle "b" times the angular interval θ and the distance between the winding axis X and the circumferential position P, and the clockwise circumferential interval between the two is calculated from an angle "Ab" times the angular interval θ and the distance between the winding axis X and the circumferential position P. Therefore, the circumferential position P (P2) of the turning point of the glass strand GS after one reciprocating movement becomes the circumferential position P offset counterclockwise by an angle "b" times the angular interval θ and the circumferential position P offset clockwise by an angle "Ab" times the angular interval θ from the circumferential position P (P1) of the turning point before reciprocating movement.

[0046] Next, the smaller value between "b" and "Ab" is the interval parameter "(A / 2) * -(A / 4) * " and above and "(A / 2) * This is explained within a specific range R below -1".

[0047] The interval parameter being within a specific range R means that the circumferential position P (P2) of the turning point of the glass strand GS after one reciprocating movement is located near the circumferential position P (P3) of the circumferential position P obtained by the turning point at the end face that is farthest from the circumferential position P (P1) of the turning point before the reciprocating movement.

[0048] The specific range R is (a) the circumferential position P (P4) (which is the circumferential position close to the circumferential position P (P1) at an angle of 1 times the angular interval θ from the circumferential position P (P3) farthest from the circumferential position P (P1)) and (b) the circumferential position P (P5) (which is (A / 4) from the circumferential position P (P3) specified in (a) above at an angular interval θ). * The angle is multiple of the circumferential position P (P1) and the circumferential position closer to the circumferential position P (P1)). Figure 3 As shown, when the number of circumferential positions P is an odd number, there are two circumferential positions P ( P3 ) farthest from the circumferential position P ( P1 ). Figure 3 , the two circumferential positions P(P3) are represented as P31(P3) and P32(P3), respectively.

[0049] When the regression coefficient is 10 or more and 17 or less, the interval parameter is preferably "(A / 2) * -2" or "(A / 2) * -1", more preferably "(A / 2) * -1". In addition, when the regression number is 18 or more, the interval parameter is preferably "(A / 2) *-3" or above and "(A / 2) * -1" or less, more preferably "(A / 2) * -2" or "(A / 2) * -1", more preferably "(A / 2) * -1".

[0050] As a first example, the regression number is "13" and the number of loop windings is "10.38". In this case, the displacement of the circumferential position P of the turning point of the glass strand GS in each reciprocating movement is as follows: Figure 4 and Figure 5 As shown. The mixed fraction of the number of cyclic windings in the first example is "10+(5 / 13)". Therefore, "b=5", "Ab=8", and the interval parameter is "5". In addition, "(A / 2) * -(A / 4) * "Above and "(A / 2) * The specific range R below -1" is "3 (=6-3)" or more and "5 (=6-1)" or less. The first example satisfies both the first condition that the regression number is 10 or more and the second condition that the interval parameter is within the specific range R.

[0051] As a second example, the regression number is "13" and the number of loop windings is "10.70". In this case, the displacement of the circumferential position P of the glass strand GS per reciprocating movement is as follows: Figure 6 As shown. The mixed fraction of the number of loop windings in the second example is "10 + (9 / 13)". Therefore, "b = 9", "Ab = 4", and the interval parameter is "4". The specific range R is "3" or greater and "5" or less, as in the first example. The second example satisfies both the first condition of a regression number of 10 or greater and the second condition of an interval parameter within the specific range R.

[0052] As a third example, the regression number is "13" and the number of loop windings is "10.16". In this case, the displacement of the circumferential position P of the glass strand GS per reciprocating movement is as follows: Figure 7 As shown. The mixed fraction of the number of cyclic windings in Example 3 is "10 + (2 / 13)". Therefore, "b = 2" and "Ab = 11", and the interval parameter is "2". The specific range R is "3" or greater and "5" or less, as in Example 1. Example 3 meets the first condition of a regression number of 10 or greater, but does not meet the second condition of the interval parameter being within the specific range R.

[0053] Thus, even if the regression number is the same, there are winding methods that satisfy the second condition related to the cyclic winding number and winding methods that do not satisfy the second condition. In the winding process of this embodiment, oblique hanging is performed according to the regression number and cyclic winding number that simultaneously satisfy the first and second conditions.

[0054] Next, the operation of this embodiment will be described.

[0055] In the method for producing the glass fiber direct yarn 10 of this embodiment, in the winding step of winding the glass strand GS into a cylindrical shape while obliquely hanging it on the rotating collet 11, the oblique hanging is performed according to the number of regressions and the number of loop windings that simultaneously satisfy the first and second conditions.

[0056] By setting the interval parameter to "(A / 2) * -(A / 4) * As described above, at the turning point of the glass strand GS formed on one end surface of the glass fiber direct yarn 10, the circumferential distance between two consecutive turning points, that is, the circumferential distance between the turning points before and after one reciprocating movement, becomes longer.

[0057] By setting the interval parameter to "(A / 2) * Below -1", at the turning points of the glass strands GS formed on one end surface of the glass fiber direct yarn 10, the distance in the radial direction between two circumferentially adjacent turning points becomes longer.

[0058] For example, Figure 5 As shown by the five arrows Y in FIG. , in the first example, the glass strand GS reciprocates five times from the circumferential position P (P1) of the initial turning point to any of the adjacent circumferential positions P (P6). In this case, the turning point at the circumferential position P (P1) and the turning point at the adjacent circumferential position P (P6) are separated in the radial direction by the amount of the five reciprocating movements of the glass strand GS.

[0059] The interval parameter is "(A / 2) * When the diameter is less than -1", the number of reciprocating movements until the turning point of the glass strand GS reaches the adjacent circumferential position is 3 or more. Therefore, the radial distance between two circumferentially adjacent turning points can be set to be at least 3 reciprocating movements.

[0060] This increases the circumferential and radial distances between the turning points of the glass strands GS at the end faces of the glass fiber direct yarn 10. This prevents interference between the turning points of the glass strands GS when the glass fiber direct yarn 10 is unwound and the glass strands GS are drawn out. Consequently, the unwound properties of the glass fiber direct yarn 10 at the end faces are improved.

[0061] In practice, an evaluation test for the unwinding properties of direct glass fiber yarns produced by the oblique winding process using the same number of return and loop windings as in Examples 1 to 3 was conducted under the following conditions. The evaluation test involved placing the direct glass fiber yarn with its axial direction horizontal on a table 1 meter above the ground and allowing the glass strands to freely fall five times. During these 10 reciprocating cycles until the strands finally fell, the number of times the strands stopped falling due to catching at the turning point was counted. The results are shown in Table 1.

[0062] Roll width of glass fiber direct yarn: 325mm

[0063] Inner diameter of glass fiber direct yarn (outer diameter of collet): 150mm

[0064] Glass fiber direct yarn count: 2400TEX

[0065] [Table 1]

[0066]

[0067] As shown in Table 1, the number of stops in the landing test was reduced in the first and second cases that satisfied both the first and second conditions, compared to the third case that did not satisfy both the first and second conditions. * In the first example of -1", the number of stops in the drop test was "0", and the result was that the relaxation property at the end surface was significantly improved.

[0068] Next, the effects of this embodiment will be described.

[0069] (1) The method for producing a glass fiber direct yarn 10 comprises a winding step of winding a glass fiber strand GS into a cylindrical shape while hanging it obliquely. In the winding step, the regression number of the oblique hanging is 10 or more, the regression number is "A", and the maximum integer less than 1 / 2 of the regression number is "(A / 2) * ", set the largest integer less than 1 / 4 of the regression number to "(A / 4) * When the number of oblique loop windings is expressed as a fraction "a+(b / A)", the smaller value between "b" and "Ab" is the interval parameter "(A / 2) * -(A / 4) * " and above and "(A / 2) * Under the condition of -1" or less, the glass strand GS is wound while hanging it obliquely.

[0070] The above configuration increases the distance between the turning points of the glass strands GS at the end faces of the glass fiber direct yarn 10. This reduces interference between the turning points of the glass strands GS when the glass fiber direct yarn 10 is unwound and the glass strands GS are drawn out, thereby improving the unwrapability of the glass fiber direct yarn 10 at the end faces.

[0071] (2) It is preferred that the interval parameter be "(A / 2) * -1" condition, while hanging it obliquely and winding the glass strand GS.

[0072] According to the above-mentioned configuration, the effect of improving the unwinding property of the glass fiber direct yarn 10 at the end surface can be more significantly obtained.

[0073] Next, the technical ideas that can be grasped from the above-mentioned embodiments are described below.

[0074] (A) A glass fiber direct yarn obtained by winding glass strands into a cylindrical shape while hanging them obliquely, wherein the regression coefficient of the oblique hanging is 10 or more, the regression coefficient is "A", and the largest integer less than 1 / 2 of the regression coefficient is "(A / 2) * ", set the largest integer less than 1 / 4 of the above regression number as "(A / 4) * When the number of oblique loop windings is expressed as a fraction "a+(b / A)", the smaller value of "b" and "Ab" is the interval parameter "(A / 2) * -(A / 4) * " and above and "(A / 2) * -1" or less.

[0075] (B) The above-mentioned glass fiber direct yarn, wherein the above-mentioned spacing parameter is "(A / 2) * -1".

[0076] (C) The method for producing the glass fiber direct yarn or the glass fiber direct yarn, wherein the winding shape is a square cheese yarn.

[0077] Explanation of symbols

[0078] GS…Glass Strand

[0079] 10…Glass fiber direct yarn

Claims

1. A method for producing a glass fiber direct yarn, comprising a winding step of winding glass strands into a cylindrical shape while hanging them obliquely, wherein: In the winding process, the regression number is a value indicating the number of times the glass strand moves around the winding axis until the circumferential position of the glass fiber direct yarn returns to the same position, with the movement of the glass strand according to the winding width of the glass fiber direct yarn being defined as one unit. The regression number of the oblique hanging is 10 or more, The regression number is set as "A", and the largest integer less than 1 / 2 of the regression number is set as "(A / 2) * ", the largest integer less than 1 / 4 of the regression number is set as "(A / 4) * ", when the number of obliquely hung loop windings is expressed as a fraction "a+(b / A)", The smaller value between "b" and "Ab" is the interval parameter "(A / 2) * -(A / 4) * "Above and" (A / 2) * Under the condition of -1" or less, the glass strands are wound while being hung obliquely.

2. The method for producing glass fiber direct yarn according to claim 1, wherein: The interval parameter is "(A / 2) * -1" condition, the glass strands were wound while being hung obliquely.

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