Quartz glass filament, quartz glass yarn, and quartz glass cloth

Abstract

To provide a quartz glass filament that effectively prevents fraying and yarn breakage of quartz glass yarn, a quartz glass yarn using the filament, and a quartz glass cloth woven using the yarn.SOLUTION: A quartz glass filament has a sizing agent attached thereto, wherein the SiO2 content of the quartz glass filament is 99.5 mass% to 100 mass%, and the ratio (r1 / r2) of the volume-average particle diameter r1 of solid particles contained in the sizing agent to the filament diameter r2 of the quartz glass filament is 0.06 to 1.0.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to quartz glass filaments, quartz glass yarns, and quartz glass cloths.

Background Art

[0002] With the recent trend of high-speed communication, quartz glass having a low dielectric tangent has attracted attention as a glass cloth used for printed wiring boards. Generally, glass yarns used for weaving are filaments coated with a sizing agent for the purpose of preventing fuzzing and yarn breakage during processing such as weaving.

[0003] Fuzz on the glass cloth is likely to cause unevenness on the surface of the prepreg, and in a printed wiring board, the copper foil laminated on this prepreg may be damaged, resulting in circuit defects. Quartz glass filaments are rigid and brittle materials, and are more likely to cause fuzzing and yarn breakage than E-glass fibers. In Patent Document 1, a sizing agent containing a urethane resin, a silane coupling agent, and wax has been proposed to improve the slipperiness during weaving. In Patent Document 2, quartz glass fibers using a cationic vinyl acetate copolymer emulsion as a sizing agent have been proposed for suppressing charging.

[0004] However, in quartz glass yarns and filaments, suppressing fuzz and improving weavability are still problems. In particular, fuzzing and yarn breakage are likely to occur when the quartz glass yarn is drawn out and unwound, which is a problem.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] The present invention has been made in view of the above circumstances, and an object thereof is to provide a fused silica filament effective in suppressing fluffing and yarn breakage of a fused silica yarn, a fused silica yarn using the fused silica filament, and a fused silica cloth woven using the fused silica yarn.

Means for Solving the Problems

[0007] In order to solve the above problems, the present invention provides a fused silica filament, a fused silica yarn, and a fused silica cloth to which the following sizing agent is attached.

[0008] That is, the present invention is a fused silica filament to which a sizing agent is attached, and the composition amount of SiO in the fused silica filament is 99.5% by mass to 100% by mass, and the ratio (r1 / r2) of the volume average particle diameter r1 of the solid particles contained in the sizing agent to the filament diameter r2 of the fused silica filament is 0.06 to 1.0. A fused silica filament is provided. 2 With such a fused silica filament of the present invention, fluffing and yarn breakage during processing such as weaving can be suppressed, and a fused silica cloth suitable for manufacturing a substrate with less transmission loss in high-speed communication and the like can be provided.

[0009]

[0010] Further, the fused silica filament of the present invention is preferably a fused silica filament characterized in that the sizing agent is a sizing agent mainly composed of any one or more of starch, polyurethane, and vinyl acetate.

[0011] Furthermore, the fused silica filament of the present invention is preferably a fused silica filament characterized in that the solid particles contained in the sizing agent contain starch.

[0012] ​These fused silica filaments of the present invention are preferable because they can prevent the occurrence of fuzzing and yarn breakage during processing such as weaving.

[0013] The present invention provides a fused silica yarn characterized by having 20 to 400 of the fused silica filaments of the present invention and having a twist of 0.1 to 5 turns per 25 mm.

[0014] Such a fused silica yarn of the present invention has no yarn breakage in the twisting process and has a small number of surface fuzz.

[0015] The fused silica yarn of the present invention preferably has a loss on ignition of 0.5 mass% to 4.0 mass% after heating at 625 °C for 2 hours.

[0016] Such a fused silica yarn is excellent in film-forming property and weavability and does not cause fuzzing or yarn breakage, so it is preferable.

[0017] Furthermore, the present invention provides a fused silica cloth characterized in that the fused silica yarn of the present invention is a warp and a weft.

[0018] Such a fused silica cloth has no yarn breakage or fuzzing, has good weavability, and is suitable as a substrate for high-speed communication with low transmission loss.

Advantages of the Invention

[0019] According to the present invention, it is possible to provide a fused silica filament and a fused silica yarn that can suppress fuzzing and yarn breakage during processing such as weaving. Further, using these, it is possible to provide a fused silica cloth suitable for manufacturing a substrate with low transmission loss in high-speed communication and the like.

Embodiments for Carrying Out the Invention

[0020] As described above, there has been a demand for the development of a fused silica filament and a fused silica yarn that can suppress fuzzing and yarn breakage during processing such as weaving, and a fused silica cloth using these.

[0021] As a result of intensive studies to achieve the above object, the inventors of the present invention have found that by controlling the ratio of the volume average particle diameter of the solid particles contained in the sizing agent to the filament diameter of the quartz glass filament within a certain range, fuzzing and thread breakage can be suppressed even in fragile quartz glass filaments, and thus the present invention has been completed.

[0022] That is, the present invention is a quartz glass filament to which a sizing agent is attached, and the SiO 2 composition amount is 99.5% by mass to 100% by mass, and the ratio (r1 / r2) of the volume average particle diameter r1 of the solid particles contained in the sizing agent to the filament diameter r2 of the quartz glass filament is 0.06 to 1.0. It is a quartz glass filament characterized by being.

[0023] Hereinafter, the present invention will be described in detail, but the present invention is not limited thereto.

[0024] [Quartz glass filament with sizing agent attached] <Quartz glass filament> The quartz glass filament of the present invention has a SiO 2 composition amount of 99.5% by mass or more, and from the viewpoints of electrical properties such as dielectric loss tangent and physical properties such as thermal expansion, SiO 2 It is preferably 99.9% by mass or more. If the SiO 2 composition amount is less than 99.5% by mass, the dielectric loss tangent deteriorates, which is not preferable.

[0025] Examples of the method for producing the quartz glass filament include the following methods.

[0026] Quartz glass with a diameter of 50 to 500 mm is melted at 1,700 to 2,300 ° C., and the filamentous material is wound up to obtain a quartz thread with a diameter of 200 ± 100 μm. If the melting temperature is within this range, stable stretching is possible.

[0027] Since the quartz fiber is very weak in strength, it is preferably coated with a coating agent for winding. As the coating agent, an acrylate resin that can be cured by UV and has excellent curability is preferred. The thickness of the coating film is preferably 5 μm or more because a sufficient reinforcing effect can be obtained. The quartz glass filament is obtained by heating the above quartz fiber to 1700 to 2300 °C in a mixed flame of oxygen and hydrogen and re-stretching it so that the filament diameter r2 becomes, for example, 3 to 15 μm thick.

[0028] The filament diameter r2 of the quartz glass filament is determined by measuring the diameter from the contour of the filament using a scanning electron microscope (VE-8800 manufactured by KEYENCE) in accordance with Method A described in 7.6.3 of JIS R 3420:2013.

[0029] <Sizing agent> The flocculant of the present invention preferably contains solid particles composed of organic molecules. The particles are not particularly limited as long as they are solid particles composed of organic molecules. For example, natural polymers such as starch, hydroxyethyl cellulose, carboxymethyl cellulose, styrene-maleic anhydride copolymer, ethylene-maleic anhydride copolymer, polyacrylamide and its derivatives, styrene-butadiene copolymer, polyvinyl acetate, polyurethane, polyacrylate, vinyl chloride-vinyl acetate copolymer, ethylene vinyl acetate copolymer, ethylene-butadiene-acrylic copolymer, polyvinylidene chloride, polylactic acid, polyarylate, liquid crystal polymer, polycarbonate, polyphenylene sulfide, polyamide, dimer acid polyamide, polytetrafluoroethylene, polyvinyl chloride, polyester, polyethyleneimine, polyoxymethylene, polyether ether ketone, polyvinyl resin, polyolefin resin, polyacrylate, polyurethane acrylate and other polymers, and synthetic polymers such as benzotriazole compounds, benzophenone compounds, triazine compounds, hindered phenol compounds, benzoate compounds, and hindered amine compounds. Among them, starch, polyurethane, or vinyl acetate is preferable, and starch is more preferable. The flocculant may be used alone or in combination of two or more kinds.

[0030] When starch, polyurethane, or vinyl acetate is used as the flocculant, it has excellent adhesion to quartz glass filaments and maintenance of flocculation properties, so it is preferable because it has the effect of suppressing the generation of fluff in the manufacturing process of quartz glass yarn and the weaving process of quartz glass cloth.

[0031] Examples of the starch include starch derived from, for example, corn, wheat, rice, potato, sweet potato, tapioca, sago, kudzu, bracken, lotus root, or beans. Among them, corn starch and rice starch with small particle diameters are preferable, and rice starch is more preferable. The starch may be used alone or in combination of two or more. Further, the starch may be unprocessed starch or processed starch. The processed starch is not particularly limited, and examples thereof include acetylated adipic acid crosslinked starch, acetylated phosphate crosslinked starch, acetylated oxidized starch, acetic acid starch, oxidized starch, hydroxypropylated starch, hydroxypropylated phosphate crosslinked starch, phosphoric acid monoesterified phosphate crosslinked starch, phosphate crosslinked starch, alpha starch, and heat-moisture treated starch.

[0032] When vinyl acetate is used as the sizing agent, cationic vinyl acetate is preferable. Cationic vinyl acetate is preferable because it can suppress the charging of quartz glass filaments and the generation of flyers in the manufacturing process of quartz glass yarns and the weaving process of quartz glass cloths.

[0033] The volume average particle diameter r1 of the solid particles contained in the sizing agent is preferably 0.15 to 15 μm. If the volume average particle diameter r1 is in the range of 0.15 to 15 μm, the buffering property and lubricity are sufficient, there is no thread breakage, and there is no occurrence of foreign matter on the filaments or hairiness.

[0034] In the present invention, the volume average particle diameter r1 of the solid particles contained in the sizing agent is the arithmetic mean value of any 20 particles measured with a scanning electron microscope (VE-8800 manufactured by KEYENCE) as the volume average particle diameter r1.

[0035] Here, the solid particles contained in the sizing agent include both the solid particles originally contained in the sizing agent raw material and the solid particles derived from other components.

[0036] [Other components] The aggregating agent of the present invention may contain components other than solid particles. Examples of other components include lubricants, emulsifiers, softeners, antistatic agents, film-forming agents, preservatives, and silane coupling agents. Further, a small amount of an alcohol such as methanol, ethanol, isopropanol or other organic solvents may be added to the aggregating agent of the present invention.

[0037] · Lubricant Examples of the lubricant include tallow, modified silicone oil, soybean oil, coconut oil, rapeseed oil, palm oil, sesame oil, paraffin, and condensates of higher saturated fatty acids and higher saturated alcohols. For animal and vegetable oils, hydrogenated hardened oils may also be used.

[0038] · Emulsifier Examples of the emulsifier include anionic surfactants, cationic surfactants, amphoteric surfactants, and nonionic surfactants.

[0039] · Softener Examples of the softener include amides, imidazolines, tetraethylenepentamine, and condensates of polyethyleneimine and stearic acid.

[0040] · Antistatic agent Examples of the antistatic agent include aliphatic polyamides, alkyl sulfonates, and quaternary ammonium salts.

[0041] The method for preparing the aggregating agent is not particularly limited, and examples include mixing with a stirring blade, a homogenizer, a static mixer, and a revolution / rotation mixer.

[0042] Based on the mass of the components other than water, the content of the solid particles originally contained in the aggregating agent raw material and those derived from other components in the aggregating agent of the present invention is preferably 10 to 95% by mass, more preferably 40 to 70% by mass. If the content of the solid particles is in the range of 10 to 95% by mass, there are buffering and lubricating effects, and no fixing occurs between the quartz glass filament and the solid particles, and no thread breakage occurs.

[0043] The ratio (r1 / r2) of the volume average particle diameter r1 of the solid particles contained in the above sizing agent to the filament diameter r2 of the quartz glass filament must satisfy 0.06 to 1.0. When the ratio of r1 / r2 is less than 0.06, the buffering effect of absorbing external impact on the quartz glass filament is impaired, and fluffing and yarn breakage occur. On the other hand, when the ratio of r1 / r2 exceeds 1.0, the adhesive force due to the particles becomes excessive when the quartz glass filament is drawn out and unwound, and fluffing and yarn breakage occur. Also, when the weft yarn is made to fly in an air jet loom or the like, there is variation, and fluff is likely to occur.

[0044] The method of applying the sizing agent to the quartz glass filament is not particularly limited, and examples include spray coating such as by spraying, roll-type or belt-type applicator coating, and dipping coating.

[0045] [Quartz glass yarn] The quartz glass strand used as the raw material of the quartz glass yarn is produced by bundling 20 to 400 quartz glass filaments. In order to bundle the quartz glass strands, the quartz glass filaments of the present invention with the sizing agent attached are used. By using the quartz glass filaments of the present invention, fluffing and yarn breakage can be suppressed when twisting the glass strands.

[0046] The quartz glass yarn is obtained by twisting the quartz glass strand. The method of twisting is not particularly limited, and a conventionally known twisting machine can be used. The frequency of twisting is preferably 0.1 times or more and 5 times or less per 25 mm, and more preferably 0.5 times or more and 1.2 times or less. If the frequency of twisting is 0.1 times or more per 25 mm, the number of twists is sufficient, so the bundling property is good, and there is no yarn breakage or fluffing, which is preferable. Also, when it is 5 times or less, the flying property and the weaving property are also good, which is preferable.

[0047] The ignition loss of the fused silica yarn of the present invention after heating at 625°C for 2 hours is preferably 0.5% by mass to 4.0% by mass. In the range of 0.5% by mass to 4.0% by mass, it is preferable because it has excellent film-forming properties and weaving properties, and does not cause hairiness or yarn breakage.

[0048] [Fused Silica Cloth] The fused silica cloth is obtained by weaving the fused silica yarn as warp and weft. The weaving apparatus is not particularly limited, and examples thereof include an air jet loom, a water jet loom, a rapier loom, and a shuttle loom. The fused silica cloth obtained by weaving the fused silica yarn of the present invention as warp and weft has no yarn breakage or hairiness and has good weaving properties.

[0049] The weave pattern, weave density, etc. of the fused silica cloth of the present invention are not particularly limited. Examples of the weave pattern include plain weave, twill weave, nanako weave, and satin weave. Further, as the weave density, for example, 10 to 130 threads / 25 mm is preferable.

[0050] The fused silica cloth of the present invention may be subjected to a fiber opening treatment. By performing the fiber opening treatment, the impregnation property and surface smoothness of a resin solution or the like when used for a prepreg or the like can be improved. The fiber opening treatment method is not particularly limited, and examples thereof include methods using ultrasonic waves, high-pressure water, diffusion spray, gas-liquid mixed mist, and the like.

[0051] The fused silica cloth of the present invention may be subjected to a degreasing treatment for removing the sizing agent after weaving. When the sizing agent remains, deterioration of dielectric properties and poor adhesion to the resin solution may occur when manufacturing a substrate. The degreasing treatment method is not particularly limited, and examples thereof include treatment by washing with water or an organic solvent, and treatment by heating.

[0052] When performing the degreasing treatment by heating, the atmosphere during heating is preferably a vacuum or a dry gas atmosphere with a dew point of 15°C or lower. Further, the heating temperature is preferably 100 to 600°C, more preferably 300 to 550°C, and still more preferably 350 to 450°C.

[0053] Also, when performing the oil removal treatment by heating, it is preferable that the weight loss during heating of the aggregating agent is larger. Specifically, it is preferable that the weight loss by heating at 400 °C for 1 hour is 90% or more.

[0054] The quartz glass cloth of the present invention is preferably subjected to a silane treatment. By performing the silane treatment, functions such as adhesiveness, flexibility, and water repellency can be imparted. From the viewpoint of more effectively exhibiting the effect of the silane treatment, it is preferable to perform the silane treatment after the oil removal treatment.

[0055] The silane treatment liquid for treating the quartz glass cloth is not particularly limited, but from the viewpoints of productivity and environmental load, an aqueous solution in which a silane coupling agent is dispersed at 0.05 to 1% by mass is preferable. A pH adjuster can be added to the silane coupling agent to form an aqueous solution. The pH adjuster is not particularly limited, but adjustment with acetic acid or ammonia is preferable according to the silane coupling agent used. The silane treatment is not particularly limited, and the quartz glass cloth to be subjected to the silane treatment may be immersed in the above treatment liquid. The temperature and time are appropriately selected from 50 to 200 °C, 30 seconds to 1 hour, etc.

[0056] When the silane treatment is performed after the oil removal step, the ignition loss of the quartz glass cloth at 625 °C for 2 hours is preferably 0.05% by mass to 0.4% by mass. In the range of 0.05% by mass to 0.4% by mass, the adhesiveness to the resin used for prepreg and the like is excellent, and the dielectric tangent does not deteriorate due to the structure of the silane coupling agent.

[0057] As silane coupling agents, there are trimethylmethoxysilane, trimethylethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, trimethoxysilane, triethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenylmethylvinylethoxysilane, naphthyltrimethoxysilane, naphthyltriethoxysilane, 1,4-bis(methoxydimethylsilyl)benzene, tetramethoxysilane, tetraethoxysilane, n-propyltriethoxysilane, hexyltrimethoxysilane, octyltriethoxysilane, decyltrimethoxysilane, 1,6-bis(trimethoxysilyl)hexane, vinyltrimethoxysilane, vinyltriethoxysilane, p-styryltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,(4-Epoxycyclohexyl)ethylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldiethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane and its hydrochloride, N-(vinylbenzyl)-2-aminoethyl-3-aminopropylmethyldimethoxysilane and its hydrochloride, 3-isocyanatopropyltriethoxysilane, tris-(trimethoxysilylpropyl)isocyanurate, 3-ureidopropyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, bis(trisethoxysilylpropyl)tetrasulfide and other alkoxysilane compounds may be mentioned, and they may be used alone or in combination of two or more. Among them, 3-aminopropyltrimethoxysilane, N-(2-(aminoethyl)-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane and the like are preferable. The silane coupling agent is not limited to these, and can be used alone or in combination of two or more.,

Examples

[0058] Hereinafter, the present invention will be specifically described using Examples and Comparative Examples, but the present invention is not limited thereto.

[0059] The measurements in the examples were carried out by the following methods. 1. The volume average particle diameter r1 of the solid particles contained in the flocculant The arithmetic mean value of any 20 particles observed with a scanning electron microscope (VE-8800 manufactured by KEYENCE) was defined as the volume average particle diameter r1. 2. The filament diameter r2 of the quartz glass filament In accordance with Method A described in 7.6.3 of JIS R 3420:2013, the diameter was measured from the filament contour using a scanning electron microscope (VE-8800 manufactured by KEYENCE). 3. The heat loss of the flocculant The prepared flocculant was dried at 100 °C for 2 hours, and using a thermogravimetric analyzer (TG-DTA8122 manufactured by RIGAKU), the weight change amount after holding at a heating rate of 20 °C / min, a maximum temperature of 400 °C for 1 hour was defined as the heat loss.

[0060] [1] Preparation of the flocculant In the examples and comparative examples, the flocculant was prepared using the following materials. · Rice starch (manufactured by Joetsu Starch, trade name: Fine Snow) · Lubricant (manufactured by NOF Corporation, trade name: Tallow 51° Hydrogenated Oil HO) · Emulsifier (manufactured by Sanyo Chemical Industries, trade name: Emalmin NL-110) · Softener (manufactured by Toho Chemical Industry, trade name: GFS-1) · Antistatic agent (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., trade name: Cationogen ES-O)

[0061] [Preparation Example 1] As components other than water, a component consisting of 40 parts by mass of rice starch, 33 parts by mass of lubricant, 7.5 parts by mass of emulsifier, 16.5 parts by mass of softener, and 3.0 parts by mass of antistatic agent was diluted with water so that the total amount became 100 parts by mass, and mixed and stirred using a homogenizer to prepare Flocculant 1. The heat loss of this Flocculant 1 at 400 °C for 1 hour was 98%.

[0062] [Preparation Example 2] As components other than water, components consisting of 70 parts by mass of rice starch, 16.5 parts by mass of a lubricant, 3.5 parts by mass of an emulsifier, 8.5 parts by mass of a softener, and 1.5 parts by mass of an antistatic agent were diluted with water so that the total amount became 100 parts by mass, and were mixed and stirred using a homogenizer to prepare Flocculant 2. The heat loss on heating of this Flocculant 2 at 400 °C for 1 hour was 98%.

[0063] [Preparation Example 3] As components other than water, components consisting of 40 parts by mass of rice starch, 33 parts by mass of a lubricant, 7.5 parts by mass of an emulsifier, 16.5 parts by mass of a softener, and 3.0 parts by mass of an antistatic agent were diluted with water so that the total amount became 100 parts by mass, and were mixed and stirred using a stirring blade to prepare Flocculant 3. The heat loss on heating of this Flocculant 3 at 400 °C for 1 hour was 98%.

[0064] [Preparation Example 4] As components other than water, components consisting of 70 parts by mass of rice starch, 16.5 parts by mass of a lubricant, 3.5 parts by mass of an emulsifier, 8.5 parts by mass of a softener, and 1.5 parts by mass of an antistatic agent were diluted with water so that the total amount became 100 parts by mass, and were mixed and stirred using a stirring blade to prepare Flocculant 4. The heat loss on heating of this Flocculant 4 at 400 °C for 1 hour was 98%.

[0065] [2] Production of quartz glass yarn [Example 1] SiO 2 Quartz glass filaments with a filament diameter of 3.5 μm were produced from quartz glass yarns with a diameter of 0.25 mm and a SiO content of 99.9 mass% or more by an oxyhydrogen flame. Flocculant 1 was applied to 100 of these quartz glass filaments to produce a quartz glass strand. The obtained quartz glass strand was twisted at a twist number of 0.6 turns / 25 mm to produce a quartz glass yarn.

[0066] [Example 2] A quartz glass yarn was produced in the same manner as in Example 1, except that Flocculant 1 in Example 1 was changed to Flocculant 2.

[0067] [Example 3] A quartz glass yarn was produced in the same manner as in Example 1, except that the filament diameter of 3.5 μm in Example 1 was changed to a quartz glass filament of 10 μm.

[0068] [Example 4] A quartz glass yarn was produced in the same manner as in Example 3, except that the filament diameter of 3.5 μm in Example 1 was changed to a quartz glass filament of 10 μm, and the sizing agent 1 was changed to sizing agent 2.

[0069] [Example 5] SiO 2 A quartz glass filament with a filament diameter of 5 μm was produced from a quartz glass thread with a diameter of 0.25 mm and a SiO content of 99.9 mass% or more by an oxyhydrogen flame. The sizing agent 3 was applied to 100 of these quartz glass filaments to produce a quartz glass strand. The obtained quartz glass strand was twisted at a twist count of 0.6 turns / 25 mm to produce a quartz glass yarn.

[0070] [Example 6] A quartz glass yarn was produced in the same manner as in Example 5, except that the sizing agent 3 in Example 5 was changed to sizing agent 4.

[0071] [Example 7] A quartz glass yarn was produced in the same manner as in Example 5, except that the filament diameter of 5 μm in Example 5 was changed to 15 μm.

[0072] [Example 8] A quartz glass yarn was produced in the same manner as in Example 5, except that the filament diameter of 5 μm in Example 5 was changed to 15 μm, and the sizing agent 3 was changed to sizing agent 4.

[0073] [Comparative Example 1] A quartz glass yarn was produced in the same manner as in Example 1, except that the filament diameter of 5 μm in Example 1 was changed to 15 μm, and the sizing agent 1 was changed to sizing agent 2.

[0074] [Comparative Example 2] A quartz glass yarn was produced in the same manner as in Example 1, except that the sizing agent 1 in Example 1 was changed to sizing agent 3.

[0075] The following evaluations were performed on the silica glass yarns obtained in each example and comparative example. The results are shown in Table 1. 1. Yarn breakage during the twisting process When twisting 100 km of silica glass strands into silica glass yarn, those without yarn breakage were marked as "〇", and those with yarn breakage during the process were marked as "×". 2. Appearance inspection of silica glass yarn The appearance of the surface of the silica glass yarn wound on the bobbin was observed by magnifying glass. Light was applied from the side of the bobbin to observe, and the number of surface hairs was measured. 3. Weavability evaluation The prepared silica glass yarn with the sizing agent attached was set on an air jet loom, and a plain weave silica glass cloth with a warp density of 60 threads / 25 mm and a weft density of 58 threads / 25 mm was woven. The weavability during weaving was evaluated according to the following criteria. · Good weavability (no yarn breakage, no hairiness): 〇 · Poor weavability (yarn breakage, hairiness): ×

[0076]

Table 1

[0077] In Examples 1 to 8 where the ratio of r1 / r2 satisfied 0.06 or more and 1.0 or less with respect to the particle diameter r1 of the solid particles contained in the sizing agent and the filament diameter r2 of the silica glass filament, there were no defects such as hairiness, and the weavability by air jet was also good.

[0078] In Comparative Example 1 where the ratio of r1 / r2 was less than 0.06, no yarn breakage was observed in the twisting process, but hairiness occurred. In Comparative Example 2 where the ratio of r1 / r2 exceeded 1.0, the adhesive force when the yarn was unwound during the twisting process was strong, and yarn breakage and hairiness occurred.

[0079] Thus, according to the present invention, by controlling the ratio of the particle diameter r1 of the solid particles contained in the sizing agent to the average filament diameter r2 of the quartz glass filament, there is a remarkable effect that a quartz glass cloth can be efficiently produced with excellent weaving properties.

[0080] This specification includes the following aspects. [1]: A quartz glass filament to which a sizing agent is attached, wherein the SiO 2 composition amount is 99.5% by mass to 100% by mass, and the ratio (r1 / r2) of the volume average particle diameter r1 of the solid particles contained in the sizing agent to the filament diameter r2 of the quartz glass filament is 0.06 to 1.0. [2]: The quartz glass filament according to [1], wherein the sizing agent is a sizing agent mainly composed of any one or more of starch, polyurethane, and vinyl acetate. [3]: The quartz glass filament according to [1] or [2], wherein the solid particles contain starch. [4]: A quartz glass yarn having 20 to 400 of the quartz glass filaments according to any one of [1] to [3], and having 0.1 to 5 twists per 25 mm. [5]: The quartz glass yarn according to [4], wherein the loss on ignition after 625 ° C. × 2 hours is 0.5% by mass to 4.0% by mass. [6]: A quartz glass cloth, wherein the quartz glass yarn according to [4] or [5] is a warp and a weft.

[0081] It should be noted that the present invention is not limited to the above 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.

Claims

1. A quartz glass filament to which a sizing agent is attached, and the SiO of the quartz glass filament ２ The composition amount is 99.5% by mass to 100% by mass, and the ratio (r1 / r2) of the volume average particle diameter r1 of the solid particles contained in the sizing agent to the filament diameter r2 of the quartz glass filament is 0.06 to 1.

0. A quartz glass filament characterized by that.

2. The quartz glass filament according to claim 1, wherein the sizing agent is a sizing agent mainly composed of any one or more components of starch, polyurethane, and vinyl acetate.

3. The quartz glass filament according to claim 1, wherein the solid particles contain starch.

4. A quartz glass yarn, comprising 20 to 400 quartz glass filaments according to claim 1 and having a twist of 0.1 to 5 turns per 25 mm.

5. The quartz glass yarn according to claim 4, wherein the loss on ignition after 625 ° C. × 2 hours is 0.5% by mass to 4.0% by mass.

6. A quartz glass cloth, wherein the quartz glass yarn according to claim 4 is a warp and a weft.

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