Quartz glass yarn package

Abstract

To provide a quartz glass yarn package in which the occurrence of fluff in a quartz glass yarn and the yarn breakage in its warping process are reduced.SOLUTION: A quartz glass yarn package comprises a bobbin having a take-up part, and a quartz glass yarn wound on the take-up part and having a SiO2 content of 95 mass% or more. The bobbin is an antistatic processed bobbin. The quartz glass yarn alternately has a portion wound from a lower portion toward an upper portion of the take-up part of the bobbin and a portion wound from the upper portion toward the lower portion of the take-up part. A winding pitch a of the portion wound from the lower portion toward the upper portion of the take-up part is 0.1 to 0.3 mm, and a winding pitch b of the portion wound from the upper portion toward the lower portion of the take-up part is 0.2 to 0.6 mm.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a quartz glass yarn package, and more specifically, to a quartz glass yarn package having excellent weaving properties.

Background Art

[0002] When weaving a glass cloth, it is common to use a glass yarn package in which a glass yarn with a twill pattern is wound around a bobbin. As the winding shape of the glass yarn package, generally, the portion from the lower part of the winding part of the bobbin to an arbitrary height above the winding part is cylindrical, and the remaining height part is in the shape of a truncated cone.

[0003] By the way, the glass yarn package has a problem that hairiness is likely to occur. One of the causes of hairiness in the glass yarn package is the chargeability of the glass fiber. In particular, in the case of quartz glass fiber with low electrical conductivity, it is remarkable as the winding amount of the bobbin increases and the diameter of the quartz glass fiber becomes thinner. In order to prevent hairiness, Patent Document 1 proposes a sizing agent for quartz glass added with an antistatic agent, but the winding amount is not mentioned, and antistatic measures when the winding amount increases are an issue.

[0004] Also, Patent Documents 2 to 4 propose glass yarn packages in which the yarn delivery property and hairiness during weaving are improved by the winding pitch and winding shape when winding the glass yarn around the bobbin. In Patent Document 2, the winding pitch with respect to the winding diameter is defined as the winding pitch ratio, and the weaving property is improved by adjusting this winding pitch ratio, but it does not mention glass yarns with a fine diameter of 3 to 5 μm in average filament diameter. In addition, in Patent Documents 3 and 4, by adjusting the height and diameter of the cylindrical portion and the height of the frustum-shaped portion of a glass yarn package with a small filament diameter having an average filament diameter of 3 to 5 μm, hairiness, yarn breakage, and unwinding collapse are reduced. However, there is no mention of fused silica glass, and suppressing hairiness and improving the weavability of hard, brittle, and highly electrostatic fused silica glass yarns have been issues.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0006] In recent years, the thickness reduction of glass cloth for printed wiring boards has been progressing, and accordingly, it is necessary for glass yarn, which is the raw yarn, to have a smaller diameter and finer count. However, fused silica glass yarns with a smaller diameter and finer count have problems such as hairiness due to the remarkable electrostatic properties and fragility of fused silica glass, and frequent yarn breakage in the warping process for preparing the warp yarns of fused silica glass cloth, making stable weaving impossible.

[0007] The present invention has been made to solve the above problems, and an object thereof is to provide a fused silica glass yarn package in which the generation of hairiness of the fused silica glass yarn and yarn breakage in the warping process are reduced, and a fused silica glass cloth woven using the fused silica glass yarn package.

Means for Solving the Problems

[0008] As a result of intensive studies to achieve the above object, the present inventors have found that a quartz glass yarn package in which the winding pitch is set to an appropriate value when winding a quartz glass yarn having a SiO2 content of 95% by mass or more around an antistatic processing bobbin can suppress hairiness due to charging, reduce thread breakage in the warping process, and not deteriorate the quality of the quartz glass cloth, and thus have completed the present invention.

[0009] Therefore, the present invention provides: 1. A bobbin having a winding portion and a quartz glass yarn having a SiO2 content of 95% by mass or more wound around the winding portion, wherein the bobbin is an antistatic processing bobbin, the quartz glass yarn alternately has a portion wound from the lower part to the upper part of the winding portion of the bobbin and a portion wound from the upper part to the lower part of the winding portion, and the winding pitch a of the portion wound from the lower part to the upper part of the winding portion is 0.1 to 0.3 mm, and the winding pitch b of the portion wound from the upper part to the lower part of the winding portion is 0.2 to 0.6 mm, a quartz glass yarn package; 2. The quartz glass yarn package according to 1, wherein the quartz glass yarn is obtained by twisting a quartz glass strand at a twist number of 0.1 to 5.0 turns / 25 mm. 3. The quartz glass yarn package according to 2, wherein the quartz glass strand is a bundle of 30 to 200 quartz glass filaments having an average diameter of 3 to 5 μm. 4. A quartz glass cloth woven using the quartz glass yarn package according to any one of 1 to 3. The present invention provides the above.

Advantages of the Invention

[0010] The quartz glass yarn package of the present invention can reduce the generation of hairiness and thread breakage during the weaving of the glass cloth. Therefore, by using the quartz glass yarn package of the present invention, a quartz glass cloth with low transmission loss for small electronic devices can be provided.

Brief Description of the Drawings

[0011]

Figure 1

Mode for Carrying Out the Invention

[0012] [Quartz Glass Yarn Package] The quartz glass yarn package of the present invention includes a bobbin having a winding portion and a quartz glass yarn having a SiO2 content of 95% by mass or more wound around the winding portion. The bobbin is subjected to antistatic treatment, and the quartz glass yarn is repeatedly wound alternately from the lower part to the upper part and from the upper part to the lower part of the winding portion at a predetermined winding pitch.

[0013] In this specification, a thin filamentary single fiber obtained by stretching a quartz glass ingot is defined as a quartz glass filament, a bundle of quartz glass filaments is defined as a quartz glass strand, a twisted quartz glass strand is defined as a quartz glass yarn, and a quartz glass yarn wound around a bobbin in a crisscross pattern is defined as a quartz glass yarn package. Also, by winding the yarn from the lower part to the upper part or from the upper part to the lower part of the winding portion of the bobbin, one yarn layer is formed. In the present invention, the distance between adjacent quartz glass yarns wound in the same layer of the bobbin winding portion is defined as the winding pitch.

[0014] (1) Bobbin The bobbin used in the present invention is not particularly limited in shape, material, etc., as long as it has a winding portion (barrel portion) for winding the quartz glass yarn, and a conventionally known one can be used. Examples of the shape of the winding portion of the bobbin used in the present invention include a cylindrical shape, a cylindrical shape, a conical shape, a frustum of a cone shape, etc. The length (height) and thickness (barrel diameter) of the winding portion are not particularly limited, and can be appropriately selected from the conventionally known ranges used for quartz glass yarn packages. Further, a plurality of convex portions (joint portions) having a trapezoidal cross-section may be formed annularly on the side surface of the winding portion at predetermined intervals along the length (height) direction.

[0015] The bobbin used in the present invention may or may not have a flange portion. When having a flange portion, it may be provided at both ends of the winding portion, or may be provided only at the lower end portion. However, from the viewpoint of weaving property, it is preferably provided only at the lower end portion. The shape of the flange portion is not particularly limited and can be appropriately selected from conventionally known shapes. For example, a disc shape, a frustum of a cone shape, a shape combining a disc shape and a frustum of a cone shape, etc. can be mentioned. Note that the orientation of the bobbin used in the present invention can be vertical, horizontal, etc. according to conditions such as during winding and during weaving, and can be appropriately selected according to the intended use.

[0016] The material of the bobbin used in the present invention is not particularly limited, and examples include acrylonitrile-butadiene-styrene (ABS) resin, 6 nylon (PA6) resin, 66 nylon (PA66) resin, polyoxymethylene (POM) resin, polycarbonate (PC) resin, polypropylene (PP) resin, etc. The manufacturing method of the bobbin is not particularly limited, and known manufacturing methods can be used.

[0017] The bobbin used in the present invention is subjected to electrostatic processing, but at least its winding portion is preferably subjected to antistatic processing. When having a flange portion, the flange portion may or may not be subjected to antistatic processing, but from the viewpoint of preventing hairiness, it is preferably subjected to antistatic processing. The antistatic processing method of the bobbin is not particularly limited, and for example, known antistatic processing methods such as a method of spraying an antistatic agent on the bobbin surface and a method of adding an antistatic agent to the resin composition before molding can be used. The type of the antistatic agent is also not particularly limited, and examples include a surfactant type and an ionomer type. In a quartz glass yarn package wound with an unprocessed anti-static bobbin, the amount of charge increases as the winding amount increases. As a result, a large number of flyers are generated on the surface of the quartz glass yarn package, and thread breakage occurs during weaving.

[0018] (2) Quartz glass yarn (2-1) Glass composition The SiO2 content of the quartz glass yarn used in the present invention is 95% by mass or more, preferably 95.0 to 100.0% by mass, more preferably 98.0 to 100.0% by mass, and still more preferably 99.0 to 100.0% by mass. Examples of components other than SiO2 include Al2O3, CaO, MgO, B2O3, and Na2O.

[0019] (2-2) Filament The quartz glass filament constitutes the quartz glass yarn and is a thin filamentary single fiber obtained by stretching a quartz glass ingot. The average diameter of the quartz glass filament used in the present invention is preferably 2 to 6 μm, more preferably 3 to 5 μm.

[0020] (2-3) Strand The quartz glass strand is a collection of quartz glass filaments. In the present invention, it is preferable to bundle 30 to 200 of the above quartz glass filaments into a strand, and more preferably 35 to 100.

[0021] (2-4) Quartz glass yarn The quartz glass yarn is obtained by twisting the quartz glass strand. In the present invention, the twist number of the quartz glass yarn is preferably 0.1 to 5.0 turns / 25 mm, more preferably 0.2 to 4.0 turns / 25 mm, and still more preferably 0.5 to 1.0 turns / 25 mm. When the twist number is less than 0.1 turn / 25 mm, the twist number is small, the bundling property is impaired, and thread breakage and flyers are likely to occur. When it exceeds 5.0 turns / 25 mm, the flying property is impaired and the weavability may be impaired.

[0022] Next, with reference to the drawings, an embodiment of the quartz glass yarn package of the present invention will be described. FIG. 1(A) shows a quartz glass yarn package 100 according to an embodiment of the present invention. The quartz glass yarn package 100 includes a bobbin 1 and a quartz glass yarn 2 wound around the bobbin 1. In this embodiment, the bobbin 1 has a winding portion 11 and a disk-shaped flange portion 12. Further, the quartz glass yarn 2 is alternately and repeatedly wound from the lower part to the upper part of the winding portion 11 of the bobbin 1 at a winding pitch a and from the upper part to the lower part at a winding pitch b. As a result, the quartz glass yarn 2 has alternately a portion 21 wound from the lower part to the upper part of the winding portion 11 of the bobbin 1 and a portion 22 wound from the upper part to the lower part. FIG. 1(B) is a partially enlarged view showing the winding pitches of the quartz glass yarn 21 wound from the lower part to the upper part of the winding portion 11 of the bobbin 1 at a winding pitch a and the quartz glass yarn 22 wound from the upper part to the lower part at a winding pitch b.

[0023] In the quartz glass yarn package of the present invention, the winding pitch a from the lower part to the upper part of the bobbin winding portion is 0.1 to 0.3 mm, preferably 0.1 to 0.2 mm. Further, the winding pitch b from the upper part to the lower part of the bobbin winding portion is 0.2 to 0.6 mm, preferably 0.2 to 0.5 mm. When the winding pitches a and b are narrower than the above ranges, the yarn feeding property is impaired, and yarn breakage and fluff are likely to occur during warping. Also, when they are wider than the above ranges, the quartz glass yarn slips off the bobbin, so that a uniform tension cannot be maintained. The winding shape of the quartz glass yarn wound around the bobbin is not particularly limited and may be appropriately selected from conventionally known shapes. For example, a cylindrical (columnar) shape, a conical shape, a frustum of a cone shape, a spindle shape, a shape combining a cylindrical (columnar) shape and a frustum of a cone shape, etc. can be mentioned. Note that the orientation of the yarn package of the present invention can be vertical, horizontal, etc. according to conditions such as during weaving and can be appropriately selected according to the use purpose.

[0024] [Method for manufacturing a quartz glass yarn package] The quartz glass yarn package of the present invention can be manufactured, for example, by a method including the following steps. As the quartz glass yarn, commercially available products with the SiO2 content within the above range can also be used. (1) Filament forming step: After molding a quartz glass ingot into a desired shape, it is heated and drawn to form a quartz glass filament. (2) Bundling step: Bundling a predetermined number of the obtained filaments to form a quartz glass strand. (3) Winding step: Twisting the obtained strand to form a quartz glass yarn while winding it around a bobbin.

[0025] (1) Filament forming step The filament forming step is a step of molding a quartz glass ingot as a raw material into a desired shape, annealing it if necessary, and then heating and drawing it to form a quartz glass filament. Examples of the method for manufacturing the raw material ingot of the quartz glass filament used in the present invention include an electric melting method and a flame melting method using quartz as a raw material; a direct synthesis method, a plasma synthesis method, and a soot method using silicon tetroxide as a raw material; a sol-gel method using alkyl silicate as a raw material, etc. However, if the SiO2 content is 95% by mass or more, it is not limited to these manufacturing methods. Among these, the electric melting method using quartz as a raw material; the plasma synthesis method, the soot method using silicon tetroxide as a raw material, or the sol-gel method using alkyl silicate as a raw material are preferred because they are less likely to contain OH groups as impurities.

[0026] The manufacturing method of the quartz glass filament used in the present invention is not particularly limited, and known spinning methods can be used. For example, there are electric melting, the stretching method of a raw material quartz ingot or quartz glass rod by a hydrogen-oxygen flame, etc. However, if the average diameter of the quartz glass filament is within the above-mentioned range, it is not limited to these manufacturing methods. For example, when manufacturing a silica glass filament using Q glass, a method of spinning a 150 - 350 μm silica glass thread stretched from an ingot raw material of silica glass by an electric furnace into a filament having the above-mentioned average diameter by a hydrogen-oxygen burner can be mentioned. Also, by controlling the diameter of the quartz glass ingot or quartz glass rod, the feeding speed of the quartz glass ingot or quartz glass rod to be stretched, and the drawing speed of the quartz glass filament, a desired filament diameter can be obtained.

[0027] (2) Bundling step The bundling step is a step of bundling a predetermined number of the obtained filaments to form a quartz glass strand. The method for forming the quartz glass strand used in the present invention is not particularly limited, and a conventionally known method can be adopted. In this case, it is preferable to apply a bundling agent when bundling the quartz glass filaments. The bundling agent used in the present invention is not particularly limited as long as it is used for quartz glass filaments. For example, a composition mainly made of starch can be mentioned. For imparting functionality, a softening agent, a lubricant, an antistatic agent, etc. can be blended. Examples of the starch include those made from corn, potato, rice, wheat, tapioca, sweet potato, etc. as raw materials.

[0028] Also, the quartz glass strand used in the present invention can also be prepared by bundling a plurality of filaments with a sizing agent. This sizing agent is usually used for the purpose of improving the bundling property of the glass filaments and protecting and preventing the flying of the glass yarn during weaving. In the present invention, a sizing agent containing a starch-based or polyvinyl alcohol (PVA)-based material as a film-forming agent component is preferable.

[0029] (3) Winding Process The winding process is a process of winding the obtained quartz glass strand onto a bobbin while twisting it using a twisting machine to form a quartz glass yarn. Here, the twisting machine used in the present invention is not particularly limited, and a conventionally known one can be used. As a specific example, for example, a plurality of rotatable spindles are vertically mounted in a row, a detachable bobbin is fitted on each spindle, and further, above each spindle, the same number of creels for mounting the cakes obtained in the spinning process are provided. A ring rail engaged with a traveler is installed around the spindle. When the twisting machine is operated, the spindle rotates at a constant speed, and accordingly, the ring rail also repeatedly moves up and down at a constant speed. By changing the winding position of the quartz glass yarn onto the bobbin, the quartz glass yarn is wound onto the bobbin from the lower part to the upper part and from the upper part to the lower part alternately at a predetermined winding pitch to obtain a quartz glass yarn package. Note that the winding pitch depends on the spindle rotation speed and the ring rail speed.

[0030] [Quartz Glass Cloth] The quartz glass cloth of the present invention is manufactured using the above quartz glass yarn package. The weave structure, weave density, etc. of the quartz glass cloth of the present invention are not particularly limited. Examples of the weave structure include plain weave, twill weave, nanako weave, damask weave, etc. Also, as the weave density, for example, 10 to 130 threads / 25 mm is preferable.

[0031] [Manufacturing Method of Quartz Glass Cloth] The manufacturing method of the quartz glass cloth of the present invention is not particularly limited and can be manufactured by a known method. For example, it can be manufactured by a method including the following steps. (11) Weaving process of manufacturing a quartz glass cloth using the quartz glass yarn package of the present invention (12) If necessary, a fiber opening process of opening the quartz glass yarn of the quartz glass cloth (13) Desizing process for removing the sizing agent used in the production of quartz glass strands, if necessary (14) Surface treatment process for treating the quartz glass cloth with a surface treatment agent, if necessary

[0032] (11) Weaving process The weaving process is a process for producing a quartz glass cloth using the quartz glass yarn package of the present invention. The weaving method is not particularly limited and can be appropriately selected from conventionally known methods. For example, those using a repair loom, a shuttle loom, an air jet loom, etc. can be mentioned.

[0033] (12) Fiber opening process The fiber opening process is a process for opening the quartz glass yarn of the quartz glass cloth, if necessary. The quartz glass cloth obtained in the weaving process can be used as it is, but if necessary, it can be fiber-opened to improve the impregnation property of the resin solution, etc. and the surface smoothness when the quartz glass cloth is used for a prepreg, etc. The fiber opening treatment method is not particularly limited, and for example, methods using ultrasonic waves, high-pressure water, diffusion spray, gas-liquid mixed mist, etc. can be mentioned.

[0034] (13) Desizing process The desizing process is a process for removing the sizing agent used in the production of quartz glass strands, if necessary. The desizing treatment method is not particularly limited, and for example, heating, water washing, etching, etc. can be mentioned.

[0035] (14) Surface treatment process The surface treatment process is a process for treating the quartz glass cloth with a surface treatment agent, if necessary. When using the quartz glass cloth of the present invention for a prepreg, etc., in order to exhibit the impregnation property of the resin composition and the adhesiveness at the interface between the resin composition and the quartz glass cloth, if necessary, the quartz glass cloth can be treated with a surface treatment agent such as a silane coupling agent.

[0036] The surface treatment agent is not particularly limited, and examples thereof include silane coupling agents having functional groups such as vinyl group, styryl group, methacryl group, and acrylic group. Specific examples of the silane coupling agent include γ-(meth)acryloxypropyl dimethoxysilane, γ-(meth)acryloxypropyl trimethoxysilane, γ-(meth)acryloxypropyl diethoxysilane, γ-(meth)acryloxypropyl triethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, p-styryltriethoxysilane, and the like. In particular, an unsaturated group-containing functional group having a stable treatment surface and capable of chemically bonding to an organic resin is preferable. For example, vinyl-based, (meth)acrylic-based, or styryl-based silane coupling agents are preferably used.

[0037] The silane coupling agent may be selected according to the glass cloth to be surface-treated or the resin used in the prepreg, and may be used alone or in combination of two or more silane coupling agents. For example, as the silane coupling agent for epoxy resin conventionally used, epoxy-based silane coupling agents, cationic silane coupling agents, and the like can be mentioned. The amount of the surface treatment agent is not particularly limited, but is preferably 0.05 to 1.0 part by mass with respect to 100 parts by mass of the quartz glass cloth.

Examples

[0038] Hereinafter, examples and comparative examples will be shown to more specifically explain the present invention, but the present invention is not limited to the following examples.

[0039] [1] Preparation of quartz glass yarn package [Example 1] 38 quartz glass rods having a SiO2 content of 95% by mass or more and a diameter of 0.25 mm were set in a jig arranged at an equal pitch, and stretching was performed with a mixed flame having a ratio of hydrogen 2 / oxygen 1 / nitrogen 0.5 (volume ratio), and a starch-based sizing agent derived from corn was applied to produce quartz glass strands having an average filament diameter of 3.6 μm × 38. A bobbin subjected to antistatic treatment was set in a ring twisting machine, and the obtained quartz glass strands were twisted at a twist count of 0.6 turns / 25 mm, with a winding pitch a from the lower part to the upper part of the bobbin winding section being 0.2 mm and a winding pitch b from the upper part to the lower part of the bobbin winding section being 0.5 mm to produce a quartz glass yarn package.

[0040] [Example 2] Thirty-eight quartz glass rods with a diameter of 0.25 mm and a SiO2 content of 95 mass% or more were set in a jig arranged at equal pitches, and stretching was performed with a mixed flame having a ratio of hydrogen 2 / oxygen 1 / nitrogen 0.5 (volume ratio). A starch-based sizing agent derived from corn was applied to produce quartz glass strands with an average filament diameter of 3.6 μm × 38 strands. A bobbin subjected to antistatic treatment was set in a ring twisting machine, and the obtained quartz glass strands were twisted at a twist count of 0.6 turns / 25 mm, with a winding pitch a from the lower part to the upper part of the bobbin winding section being 0.1 mm and a winding pitch b from the upper part to the lower part of the bobbin winding section being 0.3 mm to produce a quartz glass yarn package.

[0041] [Example 3] Thirty-eight quartz glass ingots with a diameter of 0.25 mm and a SiO2 content of 95 mass% or more were set in a jig arranged at equal pitches, and stretching was performed with a mixed flame having a ratio of hydrogen 2 / oxygen 1 / nitrogen 0.5 (volume ratio). A starch-based sizing agent made of corn was applied to produce quartz glass strands with an average filament diameter of 3.6 μm × 38 strands. A bobbin subjected to antistatic treatment was set in a ring twisting machine, and the obtained quartz glass strands were twisted at a twist count of 0.6 turns / 25 mm, with a winding pitch a from the lower part to the upper part of the bobbin winding section being 0.3 mm and a winding pitch b from the upper part to the lower part of the bobbin winding section being 0.2 mm to produce a quartz glass yarn package.

[0042] [Example 4] Set 38 quartz glass rods with a diameter of 0.25 mm and a SiO₂ content of 95 mass% or more on a jig arranged at equal pitches, and perform stretching with a mixed flame having a ratio of hydrogen 2 / oxygen 1 / nitrogen 0.5 (volume ratio). Apply a starch-based sizing agent composed of a cone to produce 38 quartz glass strands with an average filament diameter of 3.6 μm. Set an antistatic processed bobbin on a ring twisting machine, and twist the obtained quartz glass strands at a twist count of 0.6 turns / 25 mm, with a winding pitch a from the lower part to the upper part of the bobbin winding section being 0.3 mm and a winding pitch b from the upper part to the lower part of the bobbin winding section being 0.6 mm to produce a quartz glass yarn package.

[0043] [Example 5] Set 38 quartz glass rods with a diameter of 0.25 mm and a SiO₂ content of 95 mass% or more on a jig arranged at equal pitches, and perform stretching with a mixed flame having a ratio of hydrogen 2 / oxygen 1 / nitrogen 0.5 (volume ratio). Apply a starch-based sizing agent composed of a cone to produce 38 quartz glass strands with an average filament diameter of 3.6 μm. Set an antistatic processed bobbin on a ring twisting machine, and twist the obtained quartz glass strands at a twist count of 0.6 turns / 25 mm, with a winding pitch a from the lower part to the upper part of the bobbin winding section being 0.1 mm and a winding pitch b from the upper part to the lower part of the bobbin winding section being 0.2 mm to produce a quartz glass yarn package.

[0044] [Example 6] Set 38 quartz glass rods with a diameter of 0.25 mm and a SiO₂ content of 95 mass% or more on a jig arranged at equal pitches, and perform stretching with a mixed flame having a ratio of hydrogen 2 / oxygen 1 / nitrogen 0.5 (volume ratio). Apply a starch-based sizing agent composed of a cone to produce 38 quartz glass strands with an average filament diameter of 3.6 μm. Set an antistatic processed bobbin on a ring twisting machine, and twist the obtained quartz glass strands at a twist count of 0.6 turns / 25 mm, with a winding pitch a from the lower part to the upper part of the bobbin winding section being 0.1 mm and a winding pitch b from the upper part to the lower part of the bobbin winding section being 0.6 mm to produce a quartz glass yarn package.

[0045] [Example 7] 38 quartz glass rods with a diameter of 0.25 mm and an SiO2 content of 95% by mass or more were set in a jig arranged at equal pitches, and stretching was performed with a mixed flame having a ratio of hydrogen 2 / oxygen 1 / nitrogen 0.5 (volume ratio). A starch-based sizing agent in the form of a cone was applied to produce a quartz glass strand having an average filament diameter of 3.6 μm × 38 strands. A bobbin subjected to antistatic treatment was set in a ring twisting machine, and the obtained quartz glass strand was twisted at a twist count of 0.5 turns / 25 mm, with a winding pitch a from the lower part to the upper part of the bobbin winding section being 0.2 mm and a winding pitch b from the upper part to the lower part of the bobbin winding section being 0.5 mm to produce a quartz glass yarn package.

[0046] [Example 8] 38 quartz glass rods with a diameter of 0.25 mm and an SiO2 content of 95% by mass or more were set in a jig arranged at equal pitches, and stretching was performed with a mixed flame having a ratio of hydrogen 2 / oxygen 1 / nitrogen 0.5 (volume ratio). A starch-based sizing agent in the form of a cone was applied to produce a quartz glass strand having an average filament diameter of 3.6 μm × 38 strands. A bobbin subjected to antistatic treatment was set in a ring twisting machine, and the obtained quartz glass strand was twisted at a twist count of 1.0 turn / 25 mm, with a winding pitch a from the lower part to the upper part of the bobbin winding section being 0.2 mm and a winding pitch b from the upper part to the lower part of the bobbin winding section being 0.5 mm to produce a quartz glass yarn package.

[0047] [Comparative Example 1] 38 quartz glass rods with a diameter of 0.25 mm and an SiO2 content of 95% by mass or more were set in a jig arranged at equal pitches, and stretching was performed with a mixed flame having a ratio of hydrogen 2 / oxygen 1 / nitrogen 0.5 (volume ratio). A starch-based sizing agent in the form of a cone was applied to produce a quartz glass strand having an average filament diameter of 3.6 μm × 38 strands. A bobbin subjected to antistatic treatment was set in a ring twisting machine, and the obtained quartz glass strands were twisted at a twist count of 0.6 turns / 25 mm, with a winding pitch a from the lower part to the upper part of the bobbin winding section being 0.05 mm and a winding pitch b from the upper part to the lower part of the bobbin winding section being 0.15 mm to produce a quartz glass yarn package.

[0048] [Comparative Example 2] Thirty-eight quartz glass rods with a diameter of 0.25 mm and a SiO2 content of 95% by mass or more were set in a jig arranged at equal pitches, and stretching was performed with a mixed flame having a ratio of hydrogen 2 / oxygen 1 / nitrogen 0.5 (volume ratio). A starch-based sizing agent in the form of a cone was applied to produce quartz glass strands with an average filament diameter of 3.6 μm × 38. A bobbin subjected to antistatic treatment was set in a ring twisting machine, and the obtained quartz glass strands were twisted at a twist count of 0.6 turns / 25 mm, with a winding pitch a from the lower part to the upper part of the bobbin winding section being 0.4 mm and a winding pitch b from the upper part to the lower part of the bobbin winding section being 1.0 mm to produce a quartz glass yarn package.

[0049] [Comparative Example 3] Thirty-eight quartz glass rods with a diameter of 0.25 mm and a SiO2 content of 95% by mass or more were set in a jig arranged at equal pitches, and stretching was performed with a mixed flame having a ratio of hydrogen 2 / oxygen 1 / nitrogen 0.5 (volume ratio). A starch-based sizing agent in the form of a cone was applied to produce quartz glass strands with an average filament diameter of 3.6 μm × 38. A bobbin not subjected to antistatic treatment was set in a ring twisting machine, and the obtained quartz glass strands were twisted at a twist count of 0.6 turns / 25 mm, with a winding pitch a from the lower part to the upper part of the bobbin winding section being 0.2 mm and a winding pitch b from the upper part to the lower part of the bobbin winding section being 0.5 mm to produce a quartz glass yarn package.

[0050] [2] Property Evaluation The following evaluations were performed on the quartz glass strands and quartz glass yarn packages obtained in each example and comparative example. The results are shown in Table 1. 1. Thread breakage during twisting Sixty-eight kilometers of fused silica strands were twisted, and those without thread breakage were marked as "〇", while those with thread breakage during the process were marked as "×". 2. Appearance inspection of fused silica yarn packages The appearance of the surface of the fused silica yarn package was observed by magnifying glass, and the presence or absence of fluff was confirmed according to the following criteria. · Ten or fewer fluff on the appearance: 〇 · Eleven or more fluff on the appearance: × 3. Weavability evaluation The weavability when weaving a fused silica cloth using the fused silica yarn package was evaluated according to the following criteria. · Good weavability (thread breakage and fluffing present): 〇 · Poor weavability (no thread breakage and no fluffing): ×

[0051]

Table 1

[0052] In Examples 1 to 8 where the winding pitch a from the lower part to the upper part of the bobbin winding section was 0.1 to 0.3 mm and the winding pitch b from the upper part to the lower part of the bobbin winding section was 0.2 to 0.6 mm during twisting, there were no defects such as fluff, and the weavability by air jet was also good. In Comparative Example 1 where the winding pitches a and b were narrower than the above range, no appearance defects of the fused silica yarn were observed, but thread breakage and fluff occurred during weaving. In Comparative Example 2 where the winding pitches a and b were wider than the above range, a load was applied to the fused silica yarn during twisting, fluff occurred, and the weavability was also poor. Also, in Comparative Example 3 where the bobbin was not subjected to antistatic processing, thread breakage occurred during twisting, there was a lot of fluff, and the weavability was also poor.

[0053] Thus, according to the present invention, by using an antistatically processed bobbin and optimizing the winding pitch in the twisting process, there is a remarkable effect that the weavability is excellent and the fused silica cloth can be efficiently manufactured. Note that the present invention is not limited to the above-described embodiments. The above embodiments are examples, and any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and exhibits the same operational effects is included in the technical scope of the present invention.

Explanation of Reference Numerals

[0054] 1 Bobbin 11 Take-up Unit 12 Flange Portion 2 Quartz Glass Yarn 21 Quartz Glass Yarn Wound from the Lower Part to the Upper Part of the Take-up Unit 22 Quartz Glass Yarn Wound from the Upper Part to the Lower Part of the Take-up Unit 100 Quartz Glass Yarn Package a Winding Pitch from the Lower Part to the Upper Part of the Take-up Unit b Winding Pitch from the Upper Part to the Lower Part of the Take-up Unit

Claims

1. A bobbin having a winding section, and a quartz glass yarn having a SiO 2 content of 95% by mass or more, wound around the winding section The bobbin is an anti-static processed bobbin, The quartz glass yarn has portions wound from the lower part to the upper part of the winding part of the bobbin and portions wound from the upper part to the lower part of the winding part alternately, and the winding pitch a of the portion wound from the lower part to the upper part of the winding part is 0.1 to 0.3 mm, and the winding pitch b of the portion wound from the upper part to the lower part of the winding part is 0.2 to 0.6 mm. A quartz glass yarn package.

2. The quartz glass yarn package according to claim 1, wherein the quartz glass yarn is obtained by twisting quartz glass strands at a twist number of 0.1 to 5.0 turns / 25 mm.

3. The quartz glass yarn package according to claim 2, wherein the quartz glass strand is a bundle of 30 to 200 quartz glass filaments with an average diameter of 3 to 5 μm.

4. A quartz glass cloth woven using the quartz glass yarn package according to any one of claims 1 to 3.

Images