JP4110923B2 - Glass roving and manufacturing method thereof - Google Patents

Description

【００３６】
実施例及び比較例は、まず、表１に示す単繊維径を有するガラスフィラメントに、集束剤（固形分５０質量％のポリエステルエマルジョンを１０．０質量％、メタクリルシランカップリング剤を０．６質量％、カチオン系潤滑剤を０．１質量％、イオン交換水を８９．３質量％）を塗布し、ギャザリングシューを用いて集束させ表１に示す番手のガラスストランドとし、図５に示すように、ガラスストランドを、ワインダーの駆動用モータ８と連動するカム１０により往復運動するトラバース１１を経由して、表１に示すワインド数となるようにコレット９上に巻き取り、水分を約１０％含有した高さ２５０ｍｍのＤＷＲを作製した。
【００３７】
次いで、水分を除去するため、ガラスロービングを誘電加熱炉で８時間乾燥し、集束剤付着量０．４質量％、水分率０．０３質量％のＤＷＲ２０を得た。
【００３８】
表１から明らかなように、実施例１〜４は、開口部がスパイラル状に形成されているため、誘電加熱による乾燥工程においても、パンクは全く発生しなかった。
【００３９】
一方、比較例５は、ガラスロービングが密に巻かれ、開口部がないため、誘電加熱による乾燥工程において、非常に高い確率でパンクが発生した。比較例６は、開口部が形成されているものの、開口部が放射状に形成されているため、誘電加熱による乾燥工程において、１００個中、１５個のＤＷＲでパンクが観察された。
【００４０】
【発明の効果】
本発明のガラスロービングは、誘電乾燥法による乾燥工程を経ても、ＤＷＲの品質低下や生産性の低下といった問題を招くことがなく、ＤＷＲのパンクや微小破裂を防止させることが可能である。
【図面の簡単な説明】
【図１】スパイラル状に形成された開口部を持つＤＷＲ端面部から見た開口部の投影模式図。
【図２】ガラスストランドが綾巻きされたＤＷＲの概略斜視図。
【図３】図１のＤＷＲの開口部の部分拡大図。
【図４】ワインド数が３．３３３３・・・のＤＷＲを横から観察した図。
【図５】機械式ワインダーの模式図。
【図６】放射状に形成された開口部を持つＤＷＲの端面部から見た開口部の投影模式図。
【符号の説明】
１、２０ ＤＷＲ（ガラスロービング）
２、２４ 端面部
３、２１ 内表面
４、２２ 外表面
５ ガラスストランド
６、２３ 開口部
７ 最初に巻かれた位置
８ ワインダーの駆動用モータ
９ コレット
１０ 往復運動用カム
１１ トラバース
１２〜１７ 歯車[0001]
BACKGROUND OF THE INVENTION
The present invention relates to glass roving manufactured by a direct winding method.
[0002]
[Prior art]
In general, glass roving (DWR: Direct Wound Roving) manufactured by a direct winding method is a method in which a molten glass drawn from a platinum bushing having hundreds to thousands of nozzles is made from a glass of several microns to a few tens of microns. The glass filaments are stretched and coated with a sizing agent on the surface of each glass filament, and then several hundred to several thousand glass filaments are drawn to form glass strands, which are wound around a rotating collet with a twill. As a method of applying the twill, a method of reciprocating the yarn guide of the glass strand in the vicinity of the collet using a traverse is generally used. The angle formed by the glass strand with the collet and the traverse angle are determined by the speed ratio of the reciprocating motion of the traverse and the collet rotation speed. The wound glass strand is dried to evaporate moisture contained in the sizing agent and form a sizing agent coating, and after removing the inner and outer layer portions, the product is made into a product.
[0003]
In addition to DWR, glass roving includes a method of winding a molten glass once on a cake, drying, drawing several to several tens of cakes, and winding them again into a cylindrical shape. Thus, the glass roving manufactured by the method of rewinding from a cake is called the combined yarn roving in distinction from DWR. Combined yarn roving is characterized in that several to several tens of relatively thin glass strands are bundled, and is greatly different in this respect from DWR composed of one thick glass strand.
[0004]
These glass rovings are widely used as reinforcing materials for FRP molded products by forming methods such as filament winding method (FW method), drawing method, sheet molding compound method (SMC method), spray-up method, and preform method. In general, however, combined yarn roving in which thin glass strands are bundled is often used in production methods such as SMC method, spray-up method, preform method, etc., while DWR consisting of a single glass strand is FW It is often used for continuous production methods such as the method and drawing method. In particular, DWR has a great advantage in a field that requires the glass fiber evenness (the length of each glass filament wound around a glass roving is equal).
[0005]
By the way, the DWR usually has a weight of about 20 kg, and its shape is a cylindrical shape having a height (axial length) of about 250 mm and a diameter (winding diameter) of about 300 mm. It has a cylindrical collet of about 150 mm and has a thick pipe shape.
[0006]
The DWR is coated with a sizing agent containing a large amount of water in the spinning process, and therefore contains about 10% of water immediately after winding. In order to evaporate and remove about 10% of the water, it is necessary to dry the DWR.
[0007]
The drying method includes a hot air drying method in which DWR is kept in a drying furnace at 120 ° C. to 140 ° C. for several to several tens of hours for drying, and a dielectric drying method for drying in about several hours using microwaves and high frequencies (for example, patents) Reference 1). Whichever method is used, the temperature of the water inside the DWR rises due to external energy supply, and evaporates and diffuses into the air from the surface of the DWR.
[0008]
In general, when water is heated under atmospheric pressure, the evaporation rate increases as the temperature rises and it boils at 100 ° C. and does not rise any further. However, in a closed space such as a pressure cooker, the pressure rises. As a result, the temperature rises to 100 ° C. or higher. In the middle layer portion of the DWR in which the glass strands are densely wound, the evaporation of water is hindered by the glass strands. As a result, the water temperature rises to a point where the heat of vaporization of the evaporating water balances with the energy replenishment heat from the outside, and the vapor pressure inside the DWR rises accordingly. When the DWR cannot withstand this increase in vapor pressure, the DWR spreads in the height direction due to the pressure, and in an extreme case, bursting of the DWR called puncture occurs.
[0009]
This puncture increases not only due to an increase in the winding density of the DWR but also due to an increase in the amount of moisture brought into the DWR and an increase in the drying temperature due to a shortening of the drying time for efficiency. Puncture is also affected by various factors such as the slidability (slidability) of the sizing agent applied to the DWR and the angle between the collet and the glass strand (twill angle).
[0010]
The number of winds is a factor that determines the winding density and twill angle of the DWR. The number of winds represents the number of rotations of the collet between half-reciprocations of the reciprocating traverse. For example, the number of winds of 3 means that the collet has rotated 3 times while the traverse moves from the right end to the left end (or vice versa). This means that the collet has rotated 6 times while the traverse makes one round trip. Therefore, if the value of the wind number is small, the traverse angle becomes large, and the reciprocating motion of the traverse is performed at a relatively high speed. Conversely, if the value of the wind number is large, the traverse angle becomes small, The reciprocating motion of the traverse is performed at a relatively slow speed, and the glass strand is wound at a twill angle closer to a right angle with respect to the rotation axis of the collet.
[0011]
Usually, in DWR, the number of winds is 1.5-6, but if the number of winds is less than 1.5, the twill angle becomes too large and the glass strand is not wound up at a predetermined position. If it is not possible and is larger than 6, the glass strand is wound at a twill angle that is nearly perpendicular to the rotation axis of the collet, and many quality problems such as fluff and lifting occur. The height of the cylindrical DWR wound up in this way is a distance reciprocated by the traverse, and its diameter is determined by the amount of the glass strand to be wound.
[0012]
In general, the number of winds is an integer or a fraction with a relatively small numerator, such as 3, 3.333 (10/3) or 3.25 (13/4). If it is, DWR does not have a high winding density. While the traverse reciprocates the number of times equal to the denominator of the wind number, the glass strand is wound on the collet twice as many times as the numerator, and then returns to the initial winding position. For example, when the number of winds is small, such as 10/3 (3.333 ...), the glass strand is wound 10x2 = 20 times while the traverse is reciprocated 3 times, Returning to the wound position, the DWR is rolled up by repeating this process, so the shape becomes a cylindrical shape having an opening 6 with a large diamond-shaped hole as shown in FIG. 3, but the shape of the DWR is Since it collapses and the cylindrical shape cannot be maintained, the unraveling property of roving deteriorates, and the transport efficiency of DWR decreases, which is not preferable. The number of rotations of the collet (in this case, 10 × 2 = 20 times) until the glass strand returns to the initial winding position is called the regression rotation number.
[0013]
In the case of the mechanical type, the number of winds is determined by the number of gear teeth used in the winder that winds the DWR. As an example, a winder using a total of six gears A to F is shown in FIG. The collet 9 and the traverse 11 are rotated by the power transmitted through the winder driving motor 8 and the three gears 12 to 14 and 15 to 17 respectively.
[0014]
When the number of teeth of each gear A to F is a to f, the number of winds is given by a × c × e / (b × d × f). For example, the number of teeth of each gear A to F is When a = 30, b = 29, c = 28, d = 17, e = 25, and f = 13, the number of winds is 30 × 28 × 25 / (29 × 17 × 13), that is, 3.27664. The regression rotation speed is 30 × 28 × 25 × 2 = 21000 × 2 = 42000.
[0015]
As in this example, in calculating the wind number, gears having a prime number of teeth are often used as the gears B, D, and F used for the denominator. By using a prime number as the denominator, the wind number becomes a fraction that cannot be further reduced, the regression speed is not reduced, and the DWR is tightly wound without having an opening with a large diamond-shaped hole. Because it can.
[0016]
Recently, a mechanical winder that can set the desired number of winds using more gears and a winder that controls the number of winds with five or more decimal places using electric signals have been developed, which can shorten the change time. It has been.
[0017]
Thus, the number of DWR winds is an important factor in determining the shape and winding density of the DWR, and until now it has been common to produce DWRs with a high winding density in order to improve productivity and transportation efficiency. Met.
[0018]
[Patent Document 1]
Japanese Patent Publication No. 53-6255 [0019]
[Problems to be solved by the invention]
However, as disclosed in Patent Document 1, particularly when a densely wound DWR is dried by a dielectric drying method in which moisture inside the DWR evaporates almost simultaneously, evaporation of water inside the DWR is suppressed, There is a problem that the DWR tends to puncture with the increase of the vapor pressure.
[0020]
In order to prevent such DWR puncture, it is conceivable to reduce the amount of moisture brought into the DWR, extend the drying time to reduce the vapor pressure, or select a sizing agent or a twill angle that can withstand high vapor pressure. However, reduction of moisture content, restriction of bundling agent and increase of twill angle are major problems such as decrease in spinning property and increase in fluff, and extension of drying time results in decrease in production efficiency and installation of huge equipment. Remains. Moreover, although these measures do not lead to puncture, the expansion of DWR of several millimeters to 1 cm, that is, so-called micro-rupture cannot be completely prevented. The micro-ruptured DWR is difficult to distinguish as an abnormal product in the inspection process, and causes workability problems such as fluff generation and lifting when used by customers.
[0021]
In view of these problems, an object of the present invention is to provide a glass roving which does not cause DWR puncture or micro-rupture even after a drying process using a dielectric drying method.
[0022]
[Means for Solving the Problems]
As a result of conducting various experiments to solve the above problems, the present inventor has provided a small opening penetrating from the inner surface to the outer surface of the DWR in a spiral shape in a projection view seen from the glass roving end surface. However, since it evaporates easily from this opening, the vapor pressure inside the DWR is reduced, and it has been found that the puncture and microburst of the DWR can be prevented, and the present invention has been proposed.
[0023]
That is, the glass roving of the present invention is a glass roving produced by winding a glass strand into a cylindrical shape by a direct winding method, and a collet from the inner surface to the outer surface of the glass roving as the diameter of the glass roving increases. It has a diamond-shaped opening that is a single through- hole that is widened in the direction of the axis of rotation of the glass strand, and is shifted in a direction perpendicular to the axis of rotation of the collet, just above the position where the glass strand was first wound. the opening characterized in that it is a spiral in a projection view from the end face the top of the glass roving by being wound Te. In addition to the above, the glass roving of the present invention has a total number N of openings of 96.1 × h / √W <N <250.0 × h / √W (where h is the height of DWR (mm), W represents the count of glass strands (g / 1000 m). In addition to the above, the glass roving of the present invention has a DWR height h of 250 mm. Furthermore, the glass roving of the present invention is obtained through a drying step by dielectric drying in addition to the above. In addition to the above, the glass roving of the present invention is such that the product of the revolving speed and the width of the glass strand is smaller than the height h of the DWR. The glass roving manufacturing method of the present invention is a glass roving formed by penetrating from the inner surface of the glass roving to the outer surface in a glass roving manufacturing method in which glass strands are wound in a cylindrical shape by a direct winding method. The total number N of spiral openings in the projection view from the upper end face of 96.1 × h / √W <N <250.0 × h / √W (where h is the height of DWR (mm), The glass roving is formed so that W represents the count of glass strands (g / 1000 m). Moreover, the manufacturing method of the glass roving of this invention forms through the drying process by dielectric heating in addition to the above.
[0024]
With the above configuration, even when the DWR is dried by the dielectric drying method, the water evaporated at the center of the DWR can be released to the outside from the opening, and the vapor pressure at the center of the DWR is reduced to reduce the DWR. It can prevent puncture and micro burst. In other words, since the opening has a spiral shape, the distance from any position of the DWR to the opening is shortened, and the water that has become steam inside the glass roving is opened before reaching the outer surface of the glass roving. This is because it is easy to escape to the outside from the opening.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic projection view of an opening as viewed from the end face of a DWR having an opening formed in a spiral shape. 2 is a schematic perspective view of the DWR, FIG. 3 is a partially enlarged view of the opening in the DWR of FIG. 2, FIG. 4 is a view of the DWR having a wind number of 3.3333. FIG. 6 is a schematic diagram of the winder, and FIG. 6 is a schematic projection diagram of the opening as viewed from the end face of the DWR.
[0026]
In order to form the opening 6 on the surface of the DWR 1, the reciprocating motion of the collet 9 and the traverse 11 shown in FIG. 5 is performed so that the product of the revolving speed and the width of the glass strand 5 is smaller than the winding height h of the DWR 1. It is necessary to set the number of teeth of the gears 12 to 17 of the cam 10 for use. For example, in the winder shown in FIG. 5, if the number of teeth of the gears 12 to 17 of A, B, C, D, E, and F is 30, 30, 30, 30, 41, and 15 respectively, the number of winds is a. From c · e / b · d · f, it is 41/15, that is, 2.73333. This value means that the collet 9 rotates 41 × 2 = 82 while the traverse 11 is reciprocating 15 times, and after 15 reciprocations, the glass strand 5 is at the position where it was first wound (see reference numeral 7 in FIG. 4). It means to be wound directly above. That is, when the DWR1 has a height of 250 mm and 41 glass strands 5 having the same inclination with respect to the axial direction of the DWR1 are wound, and the width of the glass strand 5 is 5 mm, the height of the DWR1 A gap of 45 mm is left in the h direction. Therefore, the axial width of the diamond-shaped DWR forming the opening 6 is about 1.1 mm, that is, (250 mm−41 mm × 5) ÷ 41≈1.1 mm. The total number of openings 6 is 41 × 15 × 2 = 1230 that intersect.
[0027]
As described above, by setting the number of teeth of the gears 12 to 17 to an appropriate number of teeth, the collet is rotated by the revolving speed, and then the glass strand 5 is wound on the position 7 where the glass strand 5 is initially wound. After that, the glass strand 5 is not wound on the opening 6, in other words, as shown in FIG. 3, the openings 6 are formed one after the other on the openings 6 once formed. Specifically, the opening 6 is linearly formed so as to penetrate from the inner surface 3 to the outer surface 4. The state of the opening 6 is schematically shown in FIG. 6, and the opening 6 extends radially from the center.
[0028]
As shown in FIG. 1, the glass roving 20 of the present invention has an opening 23 formed through the glass roving 20 from the inner surface 21 to the outer surface 22 in a projection view from the upper end surface 24 of the glass roving 20. It is formed in a spiral shape. Thus, in order to form the opening 23 in a spiral shape, it is necessary to set the number of winds very close to the number of winds. For example, if the number of winds is set to 2.733320, which is close to 2.733333 ..., the glass strand will be directly above position 7 where it was first wound when the wind number is 2.733333 ... On the other hand, when the wind number is 2.73320, the difference 0.00013 is wound. That is, the glass strand rotates 41 × 2 = 82 times on the collet 9 while the traverse makes 15 reciprocations, and is wound with a shift of about 0.36 mm in the direction perpendicular to the rotation axis of the collet from the first winding position 7. After another 15 round trips, it will deviate about 0.36 mm again. As a result, the opening 23 is displaced by about 0.36 mm perpendicular to the rotation axis of the collet every 15 reciprocations, and the area of the opening 23 gradually increases as the diameter of the DWR 20 increases. Therefore, in the DWR 20 wound about 11,000 times, the opening 23 is formed in a spiral shape in the projection view from the upper end surface 24 of the glass roving 20 as shown in FIG. 6, and the position of the opening 23 on the outer surface 22 is The position of the opening 23 on the inner surface 21 is shifted by about 400 mm. Since the opening 23 formed in a spiral shape inside the DWR 20 in this way has a smaller distance from any position of the DWR 20 to the opening 23, the vapor pressure is smaller than that of the radial opening 6 shown in FIG. The effect of the reduction is greatly improved, and the occurrence of puncture can be prevented.
[0029]
In general, the total number of openings 23 is inversely proportional to the area of one opening 23. If the number of openings 23 increases, the area of one opening 23 decreases. 23 disappears due to the sliding of the glass strand. In addition, when the total number of the openings 23 is small, the winding density of the DWR 20 is lowered, and the shape is broken and the cylindrical shape cannot be maintained. Accordingly, the total number N of openings 23 formed in the DWR 20 has a desirable range, and is defined by the following equation.
96.1 × h / √W <N <250.0 × h / √W
Here, h represents the height (mm) of the DWR 20, and W represents the count of the glass strand (g / 1000 m).
[0030]
When the total number N of the openings 23 is less than 96.1 × h / √W, one area of the opening 23 is increased, the winding density is decreased, and more than 250.0 × h / √W. This is not preferable because the area of one of the openings 23 becomes too small, and the vapor pressure of water inside the DWR 20 is difficult to decrease during drying.
[0031]
In a general DWR 20, that is, a height of 250 mm and a count of 2310 tex, the desired total number N of openings 23 is 500 to 1300. The count 2310tex represents that the weight per 1000 m of the glass strand is 2310 g.
[0032]
The total number N of desirable openings 23 is, of course, proportional to the height h of the DWR 20, for example, 1000 to 2600 when the height h is doubled to 500 mm. On the other hand, regarding the diameter of the DWR 20, the desirable total number N of the openings 23 does not change. This is a single hole through which the opening 23 penetrates from the inner surface 21 to the outer surface 22, and the shape of the opening 23 becomes a rhombus that is expanded in the direction of the collet's rotation axis as the diameter of the DWR 20 increases. This is because the area of the opening 23 also increases, so that the opening ratio in the outer peripheral surface is the same in any part except the end face part 24 of the DWR 20.
[0033]
The count W of the glass strand also affects the desired total number of openings 23. When the count W of the glass strand is increased, the winding width (strand width) of the glass strand is increased. Therefore, in order to form the opening 23, the number of glass strands wound around the collet 9 is reduced, that is, the return rotation. It is necessary to reduce the number. The total number of openings 23 decreases as the revolving speed decreases. Therefore, the total number N of desirable openings 23 is inversely proportional to the width of the glass strands, and the glass strands have similar cross-sectional shapes regardless of the counts. Inversely proportional to That is, in the DWR 20 of 575 tex, which is almost a quarter of the count 2310 tex, the total number N of desirable openings 23 is doubled to 1000-2600.
[0034]
Table 1 shows Examples 1 to 4 and Comparative Examples 5 and 6 of the present invention.
[0035]
[Table 1]

[0036]
In Examples and Comparative Examples, first, a glass filament having a single fiber diameter shown in Table 1 is combined with a sizing agent (a polyester emulsion having a solid content of 50% by mass is 10.0% by mass, and a methacrylsilane coupling agent is 0.6% by mass. %, Cationic lubricant 0.1% by weight, ion-exchanged water 89.3% by weight), and gathered using a gathering shoe to form a glass strand with the count shown in Table 1, as shown in FIG. The glass strand is wound on the collet 9 through the traverse 11 reciprocatingly moved by the cam 10 interlocked with the winder driving motor 8 so as to have the wind number shown in Table 1, and contains about 10% of water. A DWR having a height of 250 mm was produced.
[0037]
Next, in order to remove moisture, the glass roving was dried in a dielectric heating furnace for 8 hours to obtain DWR20 having a sizing agent adhesion amount of 0.4 mass% and a moisture content of 0.03 mass%.
[0038]
As is clear from Table 1, in Examples 1 to 4, since the opening was formed in a spiral shape, puncture did not occur at all even in the drying process by dielectric heating.
[0039]
On the other hand, in Comparative Example 5, since the glass roving was densely wound and there was no opening, puncture occurred with a very high probability in the drying process by dielectric heating. In Comparative Example 6, although the openings were formed, the openings were formed in a radial pattern. Therefore, puncture was observed in 15 out of 100 DWRs in the drying process by dielectric heating.
[0040]
【The invention's effect】
Even if the glass roving of the present invention undergoes a drying process by a dielectric drying method, it does not cause problems such as a decrease in quality of DWR or a decrease in productivity, and it is possible to prevent puncture or micro-rupture of DWR.
[Brief description of the drawings]
FIG. 1 is a schematic projection view of an opening viewed from an end face of a DWR having an opening formed in a spiral shape.
FIG. 2 is a schematic perspective view of a DWR in which glass strands are traversed.
3 is a partially enlarged view of the opening of the DWR in FIG. 1. FIG.
FIG. 4 is a view of a DWR having a wind number of 3.3333.
FIG. 5 is a schematic view of a mechanical winder.
FIG. 6 is a schematic projection view of an opening viewed from an end surface portion of a DWR having a radially formed opening.
[Explanation of symbols]
1, 20 DWR (Glass roving)
2, 24 End face part 3, 21 Inner surface 4, 22 Outer surface 5 Glass strand 6, 23 Opening part 7 Winding position 8 Winder drive motor 9 Collet 10 Reciprocating cam 11 Traverse 12-17 Gears

Claims (7)

In glass roving manufactured by winding glass strands in a cylindrical shape by a direct winding method,
Along with the increase in the diameter of the glass roving, it is provided with a rhombus opening that is a single through- hole that is expanded in the direction of the collet rotation axis from the inner surface to the outer surface of the glass roving,
To just above the position where the glass strand is first wound, that said opening by being wound vertically offset with respect to the rotation axis of the collet is spiral in a projection view from the end face the top of the glass roving Glass roving characterized by. Total number N of openings is 96.1 × h / √W <N <250.0 × h / √W (where h is the height of DWR (mm), W is the number of glass strands (g / 1000 m)) The glass roving according to claim 1, wherein The glass roving according to claim 2, wherein the height h of the DWR is 250 mm. The glass roving according to any one of claims 1 to 3, wherein the glass roving is obtained through a drying step by dielectric drying. The glass roving according to any one of claims 2 to 4, wherein the product of the revolving speed and the width of the glass strand is smaller than the height h of the DWR. In the manufacturing method of glass roving in which glass strands are wound in a cylindrical shape by a direct winding method,
The total number N of spiral openings in the projection from the upper end face of the glass roving formed through the inner surface of the glass roving to the outer surface is 96.1 × h / √W <N <250.0. X h / √W (where h is the height of DWR (mm), W is the glass strand count (g / 1000 m)), and the glass roving is formed. Production method. It forms through the drying process by dielectric heating, The manufacturing method of the glass roving of Claim 6 characterized by the above-mentioned.

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