JP2009263824A - Quartz glass cloth - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin quartz glass cloth producible at a low cost, having improved processability and appearance and suitable for a multilayer printed circuit board for a high-frequency circuit. <P>SOLUTION: The quartz glass cloth is produced using a quartz glass yarn as warps and wefts and weaving at a yarn density of 10-95 yarns/cm for warp and weft, wherein the quartz glass yarn is obtained by bundling 15-49 quartz glass filaments having an average filament diameter of 3-9 μm to form a strand and using the strand after twisting at a twist number of ≤40 t/m or without twisting the strand. The surface of the glass cloth is coated with a silane coupling agent, both selvages of the glass cloth is subjected to fray prevention treatment, and the total filament number of the warps and wefts is 80,000-280,000 filaments/m<SP>2</SP>. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a quartz glass cloth using quartz glass fibers, and more particularly to a multilayer printed wiring board, and more particularly, to a thin quartz glass cloth used for a multilayer printed wiring board forming a high frequency circuit having a frequency of 1 GHz or more.

  In recent years, the use of high frequencies in the GHz range has been studied for IC circuits used for millimeter wave radars and the like, and some of them are being put into practical use. Printed wiring boards used in such circuits are required to have an improved relative dielectric constant and dielectric loss tangent, but these dielectric properties are large in the physical properties of glass cloth base materials used as reinforcing agents in the board. It has an effect, and when quartz glass is used as a material, very excellent characteristics can be obtained. At the same time, multilayering is progressing, and the glass cloth used for this is required to be thin. As a method for producing a thin quartz glass cloth, for example, Patent Document 1 discloses a method for producing a quartz glass cloth having a thickness of 27 μm.

On the other hand, the style of glass cloth used for printed wiring boards is the diameter of the filament used, the weight of the strands bundled with the filaments, the twisted state of the strands, the weave density of each of the warp and weft yarns, the cloth thickness, and the cloth weight. IPC-4412A is an international standard as a standard for printed circuit board E-glass that is suitably used for high-frequency multilayer printed wiring boards. In the standard, a filament having a diameter of φ4 μm to φ9 μm is used. For example, when a yarn of 7 μm is used, there is a style 2112 as the thinnest cross. This uses strands weighing 22 g per 1000 m, the density of glass strands in the cloth is 15.7 and 15.4, and the thickness of the cloth is 0.081 mm. Is 67.0 g or more and 71.0 g or less per 1 m ² .
If a 2.2 g / ^{m 3} the specific gravity of the quartz glass the specific gravity of the E-glass and 2.54 g / ^{m 3,} weight per 1 m ² of quartz glass in terms is as follows 61.5g than 58.0 g. However, quartz glass is very expensive, and its hardness is very high compared to E glass. Therefore, the drill is extremely consumed during drilling, and laser via processing is difficult. When the quartz glass cloth according to the invention is manufactured, it can only be used for a limited purpose as a printed wiring board. In order to solve this, for example, when trying to make a thinner cloth than style 2112, using 11 g of strands per 1000 m and making a cloth with the same standard as style 2112, only a coarser one can be obtained. Furthermore, fraying frequently occurs from both ears, and there has been a problem that the requirements as a substrate for a printed wiring board are not satisfied.
JP 2006-282401 A

  The present invention is sufficiently inexpensive as a quartz cloth for a high-frequency printed wiring board made of a quartz glass filament having a diameter of 9 μm or less, and has been made with the object of improving its workability and appearance, and particularly exceeds 1 GHz. An object of the present invention is to provide a thin quartz glass cloth suitably used for a multilayer printed wiring board used in a high frequency circuit, preferably a quartz glass cloth having a thickness of 45 μm or less.

In order to achieve the above object, the present inventors have made extensive studies and completed the present invention.
That is, in the quartz glass cloth of the present invention, quartz glass filaments having an average filament diameter of 3 μm or more and 9 μm or less are bundled into 15 or more and 49 or less strands, and the strands are twisted with a twist number of 40 t / m or less. Or a glass cloth formed by weaving a quartz glass yarn constructed without being subjected to a twisting treatment with a weaving density of warp yarn and weft yarn of 10 yarns / cm or more and 95 yarns / cm or less, respectively. The surface of the glass cloth is coated with a silane coupling agent, and both ears of the glass cloth are processed to prevent fraying, and the total number of filaments including warp and weft yarns is 80,000 / m ^2. The above is 280,000 pieces / m ² or less.

  The glass cloth is subjected to a fiber opening treatment, and it is preferable that the flatness of the strands constituting the glass cloth after the fiber opening treatment is 3 or more and 10 or less.

The quartz glass cloth of the present invention has a thickness of 6 μm or more and 45 μm or less before the coating with the silane coupling agent and the anti-fraying process, and the coating with the silane coupling agent and the fraying. It is preferable that the cross basis weight of the quartz glass cloth before the prevention processing is performed is 3.5 g / m ² or more and 35 g / m ² or less.

Further, the quartz glass cloth of the present invention has a cloth basis weight of 1.25 Xg / m before the coating with the silane coupling agent and the fraying prevention processing when the average filament diameter of the quartz glass filament is X μm. It is preferable that it is in the range of ² or more and 3.75 Xg / m ² or less, and the weave density of the warp yarn and the weft yarn is in the range of 90 / X pieces / cm or more and 270 / X pieces / cm or less, respectively.

  The silane coupling agent is preferably an alkoxysilane.

  The quartz glass cloth of the present invention is particularly preferably used as a printed wiring board.

  A first aspect of the method for producing a quartz glass cloth of the present invention is a non-twisted quartz composed of strands in which quartz glass filaments having an average filament diameter of 3 μm or more and 9 μm or less are bundled in a number of 15 or more and 49 or less. A step of forming glass yarn, a step of weaving the quartz glass yarn with a weaving density of warp yarn and weft yarn of 10 yarns / cm or more and 95 yarns / cm or less to form a glass cloth, The method includes a step of coating the surface with a silane coupling agent and a step of preventing fraying on both ears of the glass cloth.

  In a second aspect of the method for producing a quartz glass cloth of the present invention, a step of bundling 15 to 49 strands of quartz glass filaments having an average filament diameter of 3 μm or more and 9 μm or less to form a strand, A step of twisting at a twist number of 40 t / m or less to form a quartz glass yarn, and the quartz glass yarn is woven so that the weave density of the warp yarn and the weft yarn is 10 yarns / cm or more and 95 yarns / cm or less, respectively. It includes a step of forming a glass cloth, a step of coating the surface of the glass cloth with a silane coupling agent, and a step of fraying prevention processing on both ears of the glass cloth.

The method of manufacturing a quartz glass cloth of the present invention, it is preferable that the total number of filaments of the combined warp and weft yarn of the quartz glass cloth is 80,000 / ^{m 2} or more 280,000 present / ^{m 2} or less.

  It is preferable that the method for producing a quartz glass cloth of the present invention further includes a step of performing a fiber opening process on the glass cloth.

  According to the present invention, it is possible to manufacture a cloth with improved workability and appearance shape that can be sufficiently used as a substrate for a printed wiring board using a quartz glass fiber having a diameter of 9 μm or less. If this ultrafine quartz glass fiber having a diameter of 9 μm or less is used, it becomes possible to produce a quartz glass cloth having a thickness of 45 μm or less that is suitably used for a multilayer printed wiring board particularly used for a high-frequency circuit exceeding 1 GHz.

  Embodiments of the present invention will be described below, but these are exemplarily shown, and it goes without saying that various modifications are possible without departing from the technical idea of the present invention.

In the quartz glass cloth of the present invention, quartz glass filaments having an average filament diameter of 3 μm or more and 9 μm or less are bundled into 15 or more and 49 or less strands, and the strands are twisted at a twist number of 40 t / m or less. Or a glass cloth formed by woven a quartz glass yarn that is not subjected to twisting treatment at a weaving density of 10 warp yarns and weft yarns of 10 yarns / cm to 95 yarns / cm, The surface is coated with a silane coupling agent, and both ears of the glass cloth are subjected to fraying prevention processing, and the total number of filaments including warp yarn and weft yarn is 80,000 yarns / m ² or more and 280,000. It is characterized by being not more than book / m ² .

The quartz glass filament used in the quartz glass cloth of the present invention has an average diameter of 3 μm to 9 μm, preferably 5 μm to 9 μm, and more preferably 5 μm to 7 μm. At this time, the average diameter of the quartz glass filaments is the average of the values obtained by taking out 50 arbitrary filaments of warp yarn and weft yarn in the quartz glass cloth and measuring arbitrary positions with an optical microscope or an electron microscope. It is obtained by doing.
The method for producing the quartz glass filament is not particularly limited, but a quartz glass material obtained by introducing a quartz glass material into a burner flame and stretching it by heating is preferable. The diameter D of the quartz glass material is preferably 0.10 to 1.40 mm.
The filament obtained as described above has a diameter of φ3 μm to φ9 μm, and is 15 or more, preferably 20 or more, more preferably 25 or more, and 49 or less, preferably 45 or less, for cutting prevention and focusing during stretching. The number is bundled in the range of less than this, more preferably in the range of 40 or less, and the strand is formed while applying the primary sizing agent. If the number of filaments is less than 15, not only is it difficult to obtain a force that can withstand the tension generated in the yarn during the process, but also weaving failure due to frequent yarn breakage will deteriorate the quality of the cloth. When the number of filaments is more than 49, the spread of the filaments becomes insufficient when the fiber opening process is performed, and the possibility that workability deteriorates is increased, which is not preferable.

  The quartz glass material used for the production of the quartz glass filament is preferably a high-purity material having few impurities, and the concentration of impurities in the quartz glass material is 10 ppm in total of Na, K and Li which are alkali metals. Hereinafter, it is more preferable that B is 1 ppm or less, P is 1 ppm or less, and U is 0.1 ppb or less. At this time, the metal impurity concentration was measured by atomic absorption after removing the sizing agent.

  Quartz glass yarn obtained by twisting the strand to a twist number of 40 t / m or less or untwisted quartz glass yarn is used as a constituent yarn of the glass cloth. The reason for twisting is to prevent yarn breakage, etc., but since the secondary sizing agent is applied at the time of twisting, a covering process is applied as will be described later. 40 t / m or less is sufficient, preferably 20 t / m or less, and more preferably 10 t / m or less. Since the primary sizing agent has already been used at the time of stretching, it may be substantially untwisted. In the present invention, a state where no twisting treatment is performed is referred to as no twist. In the present invention, the number of twists is determined by a method according to JIS R3420 7-5.

The quartz glass yarn has a warp density and a weft density of 10 pieces / cm or more, preferably 12 pieces / cm or more, more preferably 15 pieces / cm or more, and 95 pieces / cm or less, preferably 40 pieces. / Cloth or less, more preferably 28 pieces / cm or less, and weaving into a glass cloth.
The weaving method of the glass cloth is not particularly limited, and examples thereof include a rapier loom, a shuttle loom, and an air jet loom.

The total number of filaments of the warp yarn and the weft yarn of the glass cloth of the present invention is 80,000 or more and 280,000 or less per 1 m ² . When the total number of filaments is less than 80,000, it is not preferable because the cross is coarse and uneven, and the strength is weak and handling becomes difficult. When the number is more than 280,000, not only is the workability deteriorated, but there is a possibility that a portion where the density of the eyes becomes excessively large due to the fiber opening process is not preferable.

The glass cloth of the present invention has a cloth basis weight of 3.5 g / m ² or more, preferably 10 g / m ² or more, and 35 g / m ² or less before being subjected to coating with a silane coupling agent and fraying prevention processing. , Preferably 18 g / m ² or less. Hereinafter, in the present specification, unless there is a special explanation, the cloth basis weight means a measurement value measured before the glass cloth is coated with the silane coupling agent and before the fraying prevention processing is performed. To do. The cloth weight measurement in the present invention is performed by a method according to JIS R 3420 7-2-2 before coating the silane coupling agent or after removing organic substances such as the silane coupling agent.

  In the present invention, when each filament diameter is selected, there are more preferable ranges for the basis weight and the weave density. The glass cloth of the present invention can further improve workability and appearance shape by maintaining the cloth basis weight and weaving density in an optimal state while satisfying the total number of filaments.

Specifically, when the filament diameter is X (unit: μm), the cloth basis weight is in the range of 50% to 150% of 2.5 × X (unit: g / m ² ), that is, 1.25X or more 3 It is preferably within a range of .75X or less (unit: g / m ² ). Table 1 shows the upper limit value and the lower limit value of a preferable range of the cloth weight per each filament diameter. As shown in Table 1, for example, when the filament diameter is φ5μm is preferable to cross basis weight and 6.25 g / ^{m 2} or more 18.75 g / ^{m 2} or less. When the cloth basis weight is less than 6.25 g / m ² , the cloth is not preferable because it is coarse and uneven, and the strength becomes weak and handling becomes difficult. A cloth having a cloth basis weight of more than 18.75 g / m ² is not preferable because problems easily occur in terms of workability and thickness uniformity.

  When the filament diameter is X (unit: μm), the weft density of the warp yarn and the weft yarn is in the range of 50% to 150% of 180 ÷ X (unit: book / cm), that is, 90 / X. It is preferably in the range of 270 / X or less (unit: book / cm). Table 2 shows the upper and lower limits of the preferred range of the weaving density at each filament diameter. As shown in Table 2, for example, when the filament diameter is φ5 μm, the weave density of the warp yarn and the weft yarn is preferably about 18 yarns / cm or more and about 54 yarns / cm or less, respectively.

  In the present invention, considering that the number of filaments in the strand is 49 at the maximum, a strand obtained by covering the strand with a yarn of another material prior to weaving may be used. Here, the material of the covering yarn is preferably one that is finally removed without causing fuzz or scratches on the quartz glass filament. Further, the covering yarn should cover the quartz glass yarn as much as possible. As a result, the quartz glass filament is not exposed on the surface during cloth weaving, and not only fuzz and yarn breakage occur, but also weaving can be performed by a normal method, and work efficiency is increased.

As a method for removing the covering yarn after weaving, common methods such as dissolution with a solution and burning off by heating can be considered, but a method of dissolving and removing with hot water using water-soluble fibers is particularly preferable. This method not only removes the covering yarn, but also spreads the filaments of the strands constituting the glass cloth, that is, a fiber opening process, and a slight gap caused by unexpectedly removing the covering yarn. Due to the presence of, the spread filament becomes wavy. For this reason, it is possible to obtain a smooth cloth having a relatively uniform roughness and a small surface irregularity in spite of a small basis weight and the number of filaments.
Further, complete removal is achieved by further heat cleaning after dissolving and removing the covering yarn.

In the present invention, it is preferable to subject the glass cloth to a fiber opening treatment after weaving. There is no particular limitation on the order of steps for performing the fiber opening treatment on the glass cloth, but it is preferable to perform the step before the coating treatment with the silane coupling agent. Further, as described above, the opening process may be performed by the covering thread removing process.
As the spread processing method, a known spread processing method can be used. For example, in Japanese Patent Laid-Open No. 61-194252, a high-pressure water jet is uniformly jetted from a plurality of nozzles onto a cloth surface to perform a fiber opening process. In particular, in the above-described covering yarn removal treatment, it is possible to perform fiber opening more efficiently by performing ultrasonic treatment in warm water.
By the fiber opening treatment, a warp yarn and a weft yarn in the strand spread and become a flat state, and a glass cloth composed of a wavy strand is obtained.

FIG. 1 is a schematic explanatory view for explaining the flatness of a strand. (A) shows a side view of a quartz glass yarn constituting the quartz glass cloth, and (b) shows a plan view of the quartz glass cloth. . In FIG. 1, 10 is a quartz glass filament, 12 is a quartz glass yarn, and 14 is a quartz glass cloth.
In the present invention, the side surface of the quartz glass cloth 14 is photographed in a plan view, and the measured value A (A in FIG. 1A) obtained by measuring the thickness of the quartz glass yarn 12 is combined with the quartz glass cloth 14. Similarly, a plane photograph of the above was taken as a plane photograph, and the ratio (B / A) of the measured value B (B in FIG. 1B) obtained by measuring the width of the quartz glass yarn 12 was determined as the flatness of the strand. Called. In the quartz glass cloth of the present invention, the flatness of the strands constituting the glass cloth after the fiber opening treatment is preferably 3 or more and 10 or less. In addition, when performing a fiber-opening process before the coating process by a silane coupling agent, an aspect ratio is also measured before the coating process by a silane coupling agent.

The quartz glass cloth of the present invention is one in which, after weaving, the glass cloth is subjected to a surface treatment with a silane coupling agent, and the surface of the glass cloth is coated with the silane coupling agent. The order of the coating process with the silane coupling agent is not particularly limited. However, when the covering described above is performed, it is preferable to perform the coating process after removing the covering yarn.
As the silane coupling agent, a known silane coupling agent can be used, but alkoxysilane is preferable, and gamma aminopropyl trimethoxy silane, gamma aminopropyl triethoxy silane, enbeta amino ethyl gamma amino propyl trimethoxy silane. 1 type or 2 types or more selected from the group consisting of enubetaaminoethyl gamma aminopropyl triethoxysilane, gamma methacryloxypropyl trimethoxysilane, gamma methacryloxypropyl triethoxysilane, trifluoropropyltrimethoxysilane are more preferable. .

  The concentration of the silane coupling agent is usually used in a dilute aqueous solution of 0.1 to 5% by weight, but it is particularly effective to use it in a range of 0.1 to 1% by weight. . By using the cloth according to the present invention, the silane coupling agent uniformly adheres to the surface of the glass cloth, and it becomes easier to handle and facilitates handling, and is also used when manufacturing a prepreg. Uniform and non-uniform coating can be applied to the resin.

The quartz glass cloth of the present invention is subjected to fraying prevention processing on both ears of the glass cloth after weaving. The order of the fraying prevention process is not particularly limited, but it is preferable to perform the fraying prevention process after the surface treatment with the silane coupling agent or simultaneously with the surface treatment. The fraying prevention process is performed in order to prevent the thread from coming off from both ears, and is preferably applied within a width of 5 mm or more and 15 mm from the end of the ear.
The fraying prevention processing method is not particularly limited, and a known method such as using a fixing material such as a polyetherimide resin, a polyester resin, a polyurethane resin, or an ethylene-vinyl acetate copolymer and gluing with a roller can be used. Since the glass cloth of the present invention has a small basis weight and a relatively loose constraint between yarns, it is essential to perform fraying prevention processing.

  According to the present invention, a thin quartz glass cloth having a thickness of 45 μm or less can be obtained. In the present invention, the thickness of the quartz glass cloth before being subjected to coating treatment with the silane coupling agent and fraying prevention processing is preferably 6 μm or more, more preferably 15 μm or more, and preferably 45 μm or less, more preferably Is 30 μm or less. In the present invention, the thickness is measured by a method according to JIS R3420 7-10.

According to the present invention, the relative permittivity of 1 MHz and 1 GHz is 3.9 or less and 4.0 or less, respectively, and the dielectric loss tangent is 1 × 10 ⁻⁴ or less and 2 × 10 ⁻⁴ or less, respectively. A quartz glass cloth having sufficient performance for a substrate can be obtained.

  The present invention will be described more specifically with reference to the following examples. However, it is needless to say that these examples are shown by way of illustration and should not be construed in a limited manner.

Example 1
A quartz glass material having a diameter D of 0.15 mm was introduced into a burner flame and heated and stretched to obtain a quartz glass strand having an average filament diameter of 6 μm and 40 filaments. At this time, an aqueous polyvinyl alcohol solution having a concentration of 1.0% was applied to the strand as a primary sizing agent. A material prepared by covering 5.5 tex of water-soluble polyvinyl alcohol fiber at 300 t / m around this strand was prepared. The quartz glass strand at this time is substantially untwisted.
Using this quartz glass covering yarn, weaving a glass cloth having a weaving density of 24 warps / cm and 24 wefts / cm in a plain weave to a width of 250 mm and a length of 400 mm using a hand-woven loom. A woven cloth having 192,000 filaments / m ² was obtained.

Next, the weaving cloth was impregnated in 70 ° C. hot water, and the covering yarn was dissolved and removed while applying ultrasonic waves for 20 minutes, followed by drying in an oven at 50 ° C. The basis weight of the cloth after drying was 13.3 g / m ² . When the quartz glass cloth was observed, although the basis weight was small, the density was relatively uniform, and a smooth cloth showing wavy undulations could be obtained. The thickness of the cloth at this time was 25 μm, and the strand flatness was 5.
Further, the glass cloth was dipped in a 0.5% aqueous solution of gamma aminopropyltrimethoxysilane, dried, and glued with a roller using an ethylene-vinyl acetate copolymer at a width of 15 mm from the ends of both ears. As a result, it was possible to obtain a cloth free from fraying from the ear.

(Example 2)
In the same manner as in Example 1, a quartz glass material was heated and stretched to obtain a quartz glass strand having an average filament diameter of 5 μm and 49 filaments. At this time, the strand was added with a 2% concentration of starch and an oil emulsion as a primary sizing agent. The strand was similarly twisted at a twist number of 10 t / m by a twisting machine while applying a secondary sizing agent having an oil emulsion added to starch at a concentration of 1.5%, and then 5.5 tex around the yarn. A water-soluble polyvinyl alcohol fiber covered with 300 t / m was prepared.
Using this quartz glass covering yarn, weaving a glass cloth with a weaving density of 25 warps / cm and 25 wefts / cm in a plain weave to a width of 250 mm and a length of 400 mm using a hand-woven loom. A woven cloth having 245,000 filaments / m ² was obtained.

Next, the weaving cloth was impregnated in 70 ° C. hot water, and the covering yarn was dissolved and removed while applying ultrasonic waves for 20 minutes, followed by drying in an oven at 50 ° C. After drying, heat treatment was performed in an air oven at 500 ° C. for 5 hours to completely remove the covering yarn. The fabric weight of this cloth was 13.0 g / m ² . When the quartz glass cloth was observed, although the basis weight was small, the density was relatively uniform, and a smooth cloth showing wavy undulations could be obtained. The strand flatness at this time was 6. The thickness of the cloth at this time was 21 μm.
Further, the glass cloth was dipped in a 0.5% aqueous solution of gamma aminopropyltrimethoxysilane, dried, and glued with a roller using an ethylene-vinyl acetate copolymer at a width of 15 mm from the ends of both ears. As a result, it was possible to obtain a cloth free from fraying from the ear.

(Example 3)
The quartz glass material was heated and stretched in the same manner as in Example 1 to obtain a quartz glass strand having an average filament diameter of φ7.5 μm and 49 filaments. At this time, a 2% concentration starch added with an oil emulsion was applied to the strand as a sizing agent. The strand was similarly twisted at a twisting number of 15 t / m by a twisting machine while giving a secondary sizing agent having an oily emulsion added to starch at a concentration of 1.5%, and 10 tex of water was then wound around the yarn. Prepared by double-covering a conductive polyvinyl alcohol fiber at 200 t / m.
Using this quartz glass covering yarn, weaving a glass cloth having a weaving density of 28 warps / cm and 28 wefts / cm in a plain weave to a width of 250 mm and a length of 400 mm using a hand-weaving loom. A woven cloth having 274,400 filaments / m ² was obtained.

Next, the weaving cloth was impregnated in 70 ° C. hot water, and the covering yarn was dissolved and removed while applying ultrasonic waves for 20 minutes, followed by drying in an oven at 50 ° C. After drying, heat treatment was performed in an atmospheric furnace at 500 ° C. for 5 hours to completely remove the covering yarn. The fabric weight of this cloth was 27.8 g / m ² . When the quartz glass cloth was observed, although the basis weight was small, the density was relatively uniform, and a smooth cloth showing wavy undulations could be obtained. At this time, the strand flatness was 5. The thickness of the cloth at this time was 32 μm.
Further, this glass cloth was dipped in a 0.5% aqueous solution of gamma aminopropyltrimethoxysilane, dried, and glued with a roller using an ethylene-vinyl acetate copolymer with a width of 15 mm from the ends of both ears. As a result, it was possible to obtain a cloth free from fraying from the ear.

Example 4
The quartz glass material was heated and stretched in the same manner as in Example 1 to obtain a quartz glass strand having an average filament diameter of 5 μm and 25 filaments. At this time, 2% concentrated starch added with an oil emulsion or the like was applied to the strand as a sizing agent. Similarly, the strand was twisted at a twisting number of 40 t / m with a twisting machine while giving a secondary sizing agent having an oil emulsion added to starch at a concentration of 1.5%.
Using this quartz glass yarn, weaving a glass cloth having a weaving density of 16 warp yarns / cm and weft yarns 16 cm / cm into a size of 250 mm wide and 400 mm long using a hand-woven loom, and the total number of filaments A woven cloth of 80,000 pieces / m ² was obtained.

Next, weaving cloth was impregnated in pure water and subjected to fiber opening treatment while applying ultrasonic waves for 20 minutes, and then dried in an oven at 50 ° C. After drying, heat treatment was performed in an atmospheric furnace at 500 ° C. for 5 hours. The fabric weight of this cloth was 4.1 g / m ² . When the quartz glass cloth was observed, although the basis weight was small, the density was relatively uniform, and a smooth cloth showing wavy undulations could be obtained. At this time, the strand flatness was 3. The thickness of the cloth at this time was 12 μm.
Further, this glass cloth was dipped in a 0.5% aqueous solution of gamma aminopropyltrimethoxysilane, dried, and glued with a roller using an ethylene-vinyl acetate copolymer with a width of 15 mm from the ends of both ears. As a result, it was possible to obtain a cloth free from fraying from the ear.

(Comparative Example 1)
A quartz glass material having an average filament diameter of 10 μm and 40 filaments was obtained by introducing a quartz glass material having a diameter D of 0.18 mm into a burner flame and drawing by heating. This strand was twisted at a twist number of 20 t / m using a twisting machine to obtain a quartz glass yarn. Using this quartz glass yarn, a glass cloth having a weaving density of 25 warps / cm and 25 wefts / cm is woven in a plain weave to a width of 250 mm and a length of 400 mm using a hand-woven loom, and the total number of filaments A woven cloth of 200,000 pieces / m ² was obtained.
The basis weight at this time was 35.2 g / m ² and the thickness of the cloth was 30 μm. The strand flatness of the cloth was 2, and the mesh was large and the filaments in the strand were in close contact, and could not be put to practical use.

(Comparative Example 2)
The quartz glass material was heated and stretched in the same manner as in Example 1 to obtain a quartz glass strand having an average filament diameter of 9 μm and 35 filaments. This strand was twisted at a twist number of 20 t / m using a twisting machine to obtain a quartz glass yarn. Using this quartz glass yarn, a glass cloth having a weaving density of 11 warps / cm and 11 wefts / cm is woven in a plain weave to a width of 250 mm and a length of 400 mm using a hand-woven loom, and the total number of filaments A woven cloth of 77,000 pieces / m ² was obtained.
The basis weight at this time was 13.2 g / m ² and the thickness of the cloth was 25 μm. When this cloth was observed, the strand flatness was 2, and the density between the strands was so large that it could not be put to practical use as a cloth.

(Comparative Example 3)
The quartz glass material was heated and stretched in the same manner as in Example 1 to obtain a quartz glass strand having an average filament diameter of 6 μm and 14 filaments. This strand was twisted at a twist number of 50 t / m using a twisting machine to obtain a quartz glass yarn. Using this quartz glass yarn, a glass cloth having a weaving density of 27 warps / cm and 27 wefts / cm is woven in a plain weave to a width of 250 mm and a length of 400 mm using a hand-woven loom, and the total number of filaments A woven cloth of 75,600 pieces / m ² was obtained.
The basis weight at this time was 5.2 g / m ² and the thickness of the cloth was 14 μm. When this cloth was observed, the strand flatness was 1.5, the density between the strands was large, and the yarn breakage during weaving frequently occurred and could not be put to practical use as a cloth.

It is the schematic explanatory drawing explaining the flatness of a strand, (a) showed the side view of the quartz glass thread | yarn which comprises a quartz glass cloth, (b) showed the top view of the quartz glass cloth.

Explanation of symbols

  10: Quartz glass filament, 12: Quartz glass yarn, 14: Quartz glass cloth.

Claims (10)

Quartz glass filaments having an average filament diameter of 3 μm or more and 9 μm or less are bundled into 15 to 49 strands to form strands, and the strands are twisted at a twist number of 40 t / m or less or are not subjected to twisting treatment. A glass cloth formed by woven a quartz glass yarn having a warp yarn density and a weft yarn density of 10 yarns / cm to 95 yarns / cm, respectively, and the surface of the glass cloth has a silane coupling agent And both ears of the glass cloth are processed to prevent fraying, and the total number of filaments combined with warp and weft is 80,000 / m ² or more and 280,000 / m ² or less. Quartz glass cloth characterized by being.   2. The quartz glass cloth according to claim 1, wherein the glass cloth has been subjected to a fiber opening treatment, and a flatness ratio of strands constituting the glass cloth after the fiber opening treatment is 3 or more and 10 or less. The quartz glass cloth before being coated with the silane coupling agent and subjected to the fraying prevention process has a thickness of 6 μm to 45 μm, and a cloth basis weight of 3.5 g / m ^{2 to} 35 g / m ² . The quartz glass cloth according to claim 1, wherein the quartz glass cloth is provided. 2. The quartz glass cloth before being subjected to the coating with the silane coupling agent and the fraying prevention processing has a cloth basis weight of 1.25 Xg / m ² or more when the average filament diameter of the quartz glass filament is X μm. The range of 75 Xg / m ² or less, and the weave density of the warp yarn and the weft yarn are in the range of 90 / X pieces / cm or more and 270 / X pieces / cm or less, respectively. The quartz glass cloth of any one of Claims.   The quartz glass cloth according to any one of claims 1 to 4, wherein the silane coupling agent is alkoxysilane.   The quartz glass cloth according to claim 1, wherein the quartz glass cloth is used for a printed wiring board. Forming an untwisted quartz glass yarn composed of strands in which quartz glass filaments having an average filament diameter of 3 μm or more and 9 μm or less are bundled in a number of 15 or more and 49 or less;
A step of weaving the quartz glass yarn with a weaving density of warp yarn and weft yarn of 10 yarns / cm or more and 95 yarns / cm or less to form a glass cloth,
Coating the surface of the glass cloth with a silane coupling agent;
A process for preventing fraying on both ears of the glass cloth;
A method for producing a quartz glass cloth, comprising: Bundling quartz glass filaments having an average filament diameter of 3 μm or more and 9 μm or less into 15 or more and 49 or less strands;
A step of twisting the strand at a twist number of 40 t / m or less to form a quartz glass yarn,
A step of weaving the quartz glass yarn with a weaving density of warp yarn and weft yarn of 10 yarns / cm or more and 95 yarns / cm or less to form a glass cloth,
Coating the surface of the glass cloth with a silane coupling agent;
A process for preventing fraying on both ears of the glass cloth;
A method for producing a quartz glass cloth, comprising: 9. The quartz glass cloth according to claim 7, wherein the total number of filaments combined with the warp and weft yarns of the quartz glass cloth is 80,000 pieces / m ² or more and 280,000 pieces / m ² or less. Manufacturing method.   The method for producing a quartz glass cloth according to any one of claims 7 to 9, further comprising a step of performing an opening treatment on the glass cloth.

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