Sizing agent for long glass fibers

Abstract

An object of the present invention is to solve the above problems and to provide a sizing agent for long glass fibers which contains an acrylic resin as a film-forming component, has an excellent effect of suppressing the generation of fluff, and also imparts excellent heat cleanability even under low-temperature conditions. (A) acrylic resin, (B) fat and oil, and (C) cationized cellulose and / or poly A sizing agent for long glass fibers, comprising an oxyethylene alkyl ether.

Description

[Technical Field]

[0001] The present invention relates to a sizing agent for long glass fibers. More specifically, the present invention relates to a sizing agent for long glass fibers that contains an acrylic resin as a film-forming component and that has an excellent effect of suppressing the generation of fluff and can impart excellent heat cleanability even at low temperatures of less than 400°C. The present invention also relates to a glass yarn prepared using the sizing agent for long glass fibers, a glass cloth using the glass yarn, and a method for producing the glass cloth. [Background technology]

[0002] Glass cloth is made of glass yarn, which is a bundle of multiple long glass fibers (filaments). Glass yarn and glass cloth for printed wiring boards are mainly produced through a glass yarn production process including a spinning process and a glass cloth production process including a warp preparation process, a weaving process, a deoiling process, and a surface treatment process. The operations in each process are as follows:

[0003] (1) Glass yarn manufacturing process (1-1) Spinning process Glass raw materials are melted in a glass melting furnace and drawn out as a plurality of long glass fibers, and the plurality of long glass fibers are bundled with a sizing agent to form a glass strand into a wound body called a cake. (1-2) Twisting process Glass strands are drawn from the cake and twisted in a twisting machine to form glass yarn. (2) Glass cloth manufacturing process (2-1) Preparation process The glass yarn is used to prepare the warp threads for the glass cloth through processes such as warping, sizing, and drawing. (2-2) Weaving process The prepared warp yarns and glass yarns as weft yarns are woven by an air jet loom or the like to produce a grey cloth. (2-3) Heat cleaning process (heat deoiling process) Sizing agents and the like applied to the surface of the long glass fibers during the spinning process can inhibit adhesion between the long glass fibers and the matrix resin during prepreg production. Therefore, a heat cleaning treatment (thermal deoiling treatment) is carried out to remove organic components such as sizing agents adhering to the glass cloth by heating. (2-4) Surface treatment process In order to improve the adhesion between the matrix resin and the long glass fibers in the prepreg manufacturing process, the heat-cleaned glass cloth is treated with a silane coupling agent.

[0004] In the glass yarn manufacturing process and the glass cloth manufacturing process described above, the long glass fibers may be partially broken, causing fluffing. The fluffing of the glass cloth may lead to defects such as poor insulation when the glass cloth is made into a printed wiring board, and therefore it is necessary to reduce the generation of fluffing. The sizing agent used in treating the long glass fibers significantly contributes to the suppression of fluffing of the glass cloth.

[0005] In sizing agents for long glass fibers, starch or synthetic resin is often used as a film-forming component. In addition, various sizing agents for long glass fibers have been proposed in the past to improve the efficiency or eliminate the need for heat cleaning treatment and to enhance the effect of suppressing the generation of fluff.

[0006] For example, Patent Document 1 reports that the use of a glass fiber yarn sizing agent containing a calcium compound can shorten the time required for heat cleaning and enable uniform heat cleaning. Specifically, Patent Document 1 shows that the use of a glass fiber yarn sizing agent containing starch and calcium acetate can promote oxidation or decomposition so that no organic matter remains, even if the oxygen supply rate is slow, and also shows that the time required for heat cleaning can be shortened.

[0007] Patent Document 2 describes how, by treating a glass fiber yarn of 1.5 to 50 tex with a sizing agent using a water-soluble epoxy resin, it is possible to remove oil by water jet processing without heat cleaning, and the yarn has a unit weight of 6 to 30 g / m. 2 They report that it is now possible to produce ultra-thin treated glass fiber fabrics.

[0008] Patent Document 3 describes a method for producing a polymer having a degree of polymerization of 3×10 2 ~1×10 5 It has been reported that by using a glass fiber sizing agent containing an acrylic copolymer, which is a sizing agent for glass fibers, it is possible to obtain glass fibers that are less likely to fluff, have excellent flying properties and hydrophilicity, and can be degreased by washing with water. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Application Publication No. 11-106241 [Patent Document 2] Japanese Patent Application Publication No. 9-67757 [Patent Document 3] Japanese Patent Application Laid-Open No. 2007-217252 Summary of the Invention [Problem to be solved by the invention]

[0010] In recent years, with the miniaturization of electronic devices, printed wiring boards are being required to be thinner. To manufacture printed wiring boards, prepregs, which are glass cloths impregnated with resin, are used. However, with the trend toward thinner printed wiring boards, the prepregs are also being required to be thinner. For example, the thickness of the prepregs is being required to be 20 μm or less. Similarly, the glass cloths contained in the prepregs are also being required to be thinner.

[0011] According to the investigations of the present inventors, in sizing agents for long glass fibers used in the glass yarn manufacturing process and the glass cloth manufacturing process, the use of starch as a film-forming component has a higher effect of suppressing the generation of fluff than the use of a synthetic resin. In printed wiring board applications where suppression of fluff generation is highly required, it is common to use starch as a film-forming component as a sizing agent for the long glass fibers that constitute the glass cloth.

[0012] For example, when starch is used as a film-forming component, as in the case of the long glass fiber sizing agent disclosed in Patent Document 1, a heat cleaning treatment must be carried out at a high temperature of 400°C or higher in order to remove the long glass fiber sizing agent adhered to the greige cloth. Heat cleaning treatments under such high temperature conditions have the disadvantage of reducing the tensile strength of the long glass fiber, glass yarn, and glass cloth. The present inventors have found that this effect becomes particularly significant when the long glass fiber and glass yarn are made thinner to produce a thinner glass cloth.

[0013] Furthermore, the sizing agents for long glass fibers disclosed in Patent Documents 2 and 3 can be deoiled by washing with water, and therefore the resulting glass cloth has almost no problem of reduced strength. However, the present inventors have found that the sizing agents for long glass fibers disclosed in Patent Documents 2 and 3 cannot be sufficiently removed by deoiling with water, and that the effect of suppressing the generation of fluff, which is strongly desired when producing thin glass cloth for printed wiring boards, is not sufficient.

[0014] Conventionally, the most common approach to improving the strength of glass cloth is to consider the glass composition. For example, it is known to use high-strength S-glass or T-glass instead of the general-purpose E-glass as the glass material constituting the glass fiber.

[0015] On the other hand, the present inventors have come up with an approach different from that based on the glass composition to address the problem of the strength reduction caused by the heat cleaning treatment of thin glass cloth, namely, to suppress the strength reduction even in a general-purpose E-glass composition by adopting lower temperature conditions in the heat cleaning treatment than in the past. That is, they have come up with the idea of ​​suppressing the strength reduction caused by the heat cleaning treatment by using a synthetic resin with good heat cleaning properties as a film-forming component of a sizing agent for long glass fibers and setting the temperature conditions for the heat cleaning treatment lower than in the past.

[0016] Therefore, the present inventors conducted extensive research and discovered the use of an acrylic resin, which allows heat cleaning at relatively low temperatures, as a film-forming component. However, further research by the present inventors revealed that when an acrylic resin is used as a film-forming component, the effect of suppressing fuzz generation is insufficient. That is, the present inventors discovered that a sizing agent for long glass fibers containing only an acrylic resin not only fails to suppress fuzz generation, but also frequently causes fiber breakage during the spinning process, making it impossible to even obtain glass strands. Furthermore, when the inventors investigated blending an oil agent as an auxiliary with the acrylic resin into the sizing agent for long glass fibers, they found that the suppression of fuzz generation was insufficient and that heat cleaning properties at low temperatures were sometimes reduced, making it difficult to achieve both a good fuzz suppression effect and good heat cleaning properties.

[0017] Therefore, an object of the present invention is to solve the above problems and to provide a sizing agent for long glass fibers which contains an acrylic resin as a film-forming component, has an excellent effect of suppressing the generation of fluff, and also imparts excellent heat cleanability even under low-temperature conditions. [Means for solving the problem]

[0018] The present inventors conducted extensive research to solve the above problems and found that a glass fiber sizing agent containing an acrylic resin, an oil, and a cationized cellulose and / or a polyoxyethylene alkyl ether has excellent fuzz suppression effects and can fully satisfy the properties required for producing thin glass cloth for printed wiring boards. Furthermore, the inventors found that this glass fiber sizing agent also has excellent heat cleaning properties even at low temperatures, exhibiting excellent heat cleaning properties even when subjected to heat cleaning treatment at temperatures below 400°C, and can suppress coloration caused by remaining organic matter (components of the glass fiber sizing agent) after heat cleaning treatment, thereby avoiding a decrease in strength due to heat cleaning treatment at high temperatures. The present invention was completed based on these findings and through further research.

[0019] That is, the present invention provides the following aspects. Item 1. (A) acrylic resin, (B) fat and oil, and (C) cationized cellulose and / or polyoxyethylene A sizing agent for long glass fibers, comprising a diethylene alkyl ether. Item 2. A glass yarn comprising a long glass fiber having a coating formed on the surface thereof, the coating containing (A) an acrylic resin, (B) an oil, and (C) a cationized cellulose and / or a polyoxyethylene alkyl ether. Item 3. A glass cloth formed from glass yarns made by bundling long glass fibers, the glass material constituting the long glass fibers is E glass or a glass composition having a dielectric constant of less than 5.0 at a frequency of 1 MHz, The tensile strength of the glass yarn is 0.50 N / tex or more, and The ignition loss of the glass cloth is 0.10% by mass or less. Glass cloth. Item 4. The glass cloth according to Item 3, which is used as a constituent material of a printed wiring board. Item 5. A method for producing glass cloth, comprising the following steps A and B: Step A: A step of weaving a gray cloth using the glass yarn described in item 2 as a warp and a weft. Step B: A step of subjecting the green cloth to heat cleaning treatment. Item 6. The method for producing a glass cloth according to Item 5, wherein the heat cleaning treatment in step B is carried out at a temperature of 280 to 330°C. [Effects of the Invention]

[0020] The sizing agent for long glass fibers of the present invention has an excellent effect of suppressing the generation of fluff, and therefore can provide a glass yarn suitable as a raw material yarn for thin glass cloth used in printed wiring boards. Furthermore, the sizing agent for long glass fibers of the present invention has good heat cleaning properties at low temperatures of less than 400°C, so that the use of this sizing agent for long glass fibers makes it possible to employ a heat cleaning treatment at low temperatures in the production of glass cloth, thereby suppressing the decrease in tensile strength of the glass yarn that occurs in conventional heat cleaning treatments at high temperatures. DETAILED DESCRIPTION OF THE INVENTION

[0021] 1. Sizing agent for long glass fibers The sizing agent for long glass fibers of the present invention is characterized by containing (A) an acrylic resin, (B) an oil or fat, and (C) a cationized cellulose and / or a polyoxyethylene alkyl ether. By containing these three components together, the sizing agent for long glass fibers of the present invention is able to exhibit an excellent effect of suppressing the generation of fluff, and also has good heat cleaning properties at low temperatures below 400°C, making it possible to avoid a decrease in strength due to heat cleaning treatment at high temperatures. The sizing agent for long glass fibers of the present invention will be described in detail below.

[0022] In this specification, "heat cleaning property" means the ability to remove non-volatile organic components (non-volatile organic components derived from sizing agents for long glass fibers, etc.) adhering to the glass yarn by heat cleaning treatment.

[0023] [(A) Acrylic resin] The sizing agent for long glass fibers of the present invention contains an acrylic resin (sometimes simply referred to as "component (A)") as a film-forming component. The acrylic resin used in the present invention is preferably one that can form an emulsion in water.

[0024] Acrylic resins are polymers obtained by polymerizing (meth)acrylic acid and / or (meth)acrylic acid derivatives as polymerizable monomers. In this specification, "(meth)acrylic acid" is a compound name that includes both acrylic acid and methacrylic acid.

[0025] Specific examples of (meth)acrylic acid include acrylic acid and methacrylic acid.

[0026] The (meth)acrylic acid derivative may be any derivative capable of radical polymerization, and examples thereof include carboxyl group-containing (meth)acrylic acid monomers such as β-carboxyethyl (meth)acrylate, 2-(meth)acryloylpropionic acid, β-(meth)acryloyloxyethyl hydrogen succinate, and salts thereof; methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. (Meth)acrylic acid ester monomers such as hexyl (meth)acrylate, cyclohexyl (meth)acrylate, octyl (meth)acrylate, nonyl (meth)acrylate, dodecyl (meth)acrylate, stearyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, phenyl (meth)acrylate, and benzyl (meth)acrylate; 2,2,2-trifluoroethyl (meth)acrylate, 2,2,3,3-tetrafluoropropyl (meth)acrylate, Fluorine-containing (meth)acrylic acid monomers such as perfluorocyclohexyl (meth)acrylate, 2,2,3,3-tetrafluoropropyl (meth)acrylate, and β-(perfluorooctyl)ethyl (meth)acrylate; glycidyl group-containing (meth)acrylic acid monomers such as glycidyl (meth)acrylate; hydroxyl group-containing monomers such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, polyethylene glycol mono(meth)acrylate, and glycerol mono(meth)acrylate. (Meth)acrylic acid-based monomers containing an amino group; (meth)acrylic acid-based monomers containing an amino group such as aminoethyl (meth)acrylate, N-monoalkylaminoalkyl (meth)acrylate, and N,N-dialkylaminoalkyl (meth)acrylate; (meth)acrylic acid-based monomers containing an aziridinyl group such as 2-aziridinylethyl (meth)acrylate; (meth)acrylic acid-based monomers containing an allyl group such as allyl (meth)acrylate; (meth)acrylic acid-based monomers containing a cyclopentenyl group such as dicyclopentenyl (meth)acrylate;Di(meth)acrylic acid monomers such as ethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, diallyl phthalate, and divinylbenzene; (meth)acrylic acid monomers containing a methylolamide group or an alkoxylated product thereof such as N-methylol(meth)acrylamide, N-isopropoxymethyl(meth)acrylamide, N-butoxymethyl(meth)acrylamide, and N-isobutoxymethyl(meth)acrylamide; γ-(meth)acryloxypropyltrimethoxysilane, γ-(meth)acryloxypropyltriethoxysilane, γ-(meth)acryloxypropyl Examples of suitable monomers include silyl group-containing (meth)acrylic acid monomers such as propylmethyldimethoxysilane, γ-(meth)acryloxypropylmethyldiethoxysilane, and γ-(meth)acryloxypropyltriisopropoxysilane; isocyanate group- and / or blocked isocyanate group-containing (meth)acrylic acid monomers such as (meth)acryloyl isocyanate and (meth)acryloyl isocyanate ethyl phenol or methyl ethyl ketoxime adducts; amide group-containing (meth)acrylic acid monomers such as (meth)acrylamide, N-monoalkyl(meth)acrylamide, and N,N-dialkyl(meth)acrylamide; carbonyl group-containing (meth)acrylic acid monomers such as diacetone(meth)acrylamide; and acetoacetyl group-containing (meth)acrylic acid monomers such as acetoacetoxyethyl(meth)acrylate.

[0027] In the acrylic resin used in the present invention, one of (meth)acrylic acid and (meth)acrylic acid derivatives may be used alone as the polymerizable monomer, or two or more of these may be used in combination.

[0028] The acrylic resin used in the present invention may be a homopolymer obtained by polymerizing only one of (meth)acrylic acid and (meth)acrylic acid derivatives, a copolymer obtained by polymerizing two or more of (meth)acrylic acid and (meth)acrylic acid derivatives, or a copolymer obtained by polymerizing one or more of (meth)acrylic acid and (meth)acrylic acid derivatives with one or more other polymerizable monomers.

[0029] When the acrylic resin is a copolymer of (meth)acrylic acid and / or a (meth)acrylic acid derivative with another polymerizable monomer, the other polymerizable monomer is not particularly limited as long as it is copolymerizable with (meth)acrylic acid and / or a (meth)acrylic acid derivative, and examples thereof include crotonic acid, itaconic acid, maleic acid, fumaric acid, itaconic acid, maleic acid, maleic anhydride, itaconic anhydride, half esters thereof, and salts thereof; unsaturated dicarboxylic acid polymerizable monomers; glycidyl group-containing polymerizable monomers such as allyl glycidyl ether; vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, γ-(meth)acryloxypropyltrimethoxysilane, γ-(meth)acryloxypropyltriethoxysilane, N-β-(N-vinylbenzylaminoethyl)-γ-aminopropyltrimethoxysilane and the like. oxazoline group-containing polymerizable monomers such as 2-isopropenyl-2-oxazoline and 2-vinyl-2-oxazoline; carbonyl group-containing polymerizable monomers such as acrolein; vinyl sulfonic acid-based polymerizable monomers such as vinyl sulfonic acid and styrene sulfonic acid; vinyl ester-based polymerizable monomers such as vinyl acetate, vinyl propionate, vinyl butyrate, and vinyl versatate; vinyl ether-based polymerizable monomers such as methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, amyl vinyl ether, and hexyl vinyl ether; aromatic vinyl compound-based polymerizable monomers such as styrene, α-methylstyrene, vinyltoluene, vinylanisole, α-halostyrene, vinylnaphthalene, and divinylstyrene; isoprene, chloroprene, butadiene, ethylene, tetrafluoroethylene, vinylidene fluoride, and N-vinylpyrrolidone. These polymerizable monomers may be used alone or in combination of two or more.

[0030] In the sizing agent for long glass fibers of the present invention, one type of acrylic resin may be used alone, or two or more types may be used in combination.

[0031] The average particle size (median size) of the acrylic resin used in the present invention is not particularly limited, but may be, for example, about 100 to 1500 nm. If the average particle size of the acrylic resin is within this range, the drying properties of the film during film formation can be improved. In the present invention, the average particle size of the acrylic resin is a value measured under the following conditions using a dynamic light scattering photometer (LPA system; ELSZ-2000ZS, manufactured by Otsuka Electronics). After diluting the resin emulsion with distilled water to a measurable concentration, the solution is filled into a four-sided transmission type 10 mm square cell, and measurement is performed by irradiating a He-Ne laser at 25°C to determine the number average particle size value.

[0032] The molecular weight of the acrylic resin used in the present invention is not particularly limited, but may be, for example, a weight average molecular weight of 1,000 to 1,000,000, preferably 2,000 to 500,000, and more preferably 100,000 to 500,000, as determined by GPC in terms of polystyrene. In the present invention, the weight average molecular weight of the acrylic resin is a value measured under the following conditions. GPC equipment: Prominence manufactured by Shimadzu Corporation Columns: SHODEX KF-800P, KF-005, KF-003, KF-001 (four columns used in series) Mobile phase: tetrahydrofuran Flow rate: 1mL / min Column oven temperature: 40°C Detector: RI Molecular weight conversion: Standard polystyrene

[0033] Furthermore, for the acrylic resin used in the present invention, the weight loss rate at 330°C in TGA (thermogravimetric analysis) is not particularly limited, but may be, for example, 95% by mass or more, preferably 98.0 to 99.9% by mass. In the present invention, the weight loss rate at 330°C in TGA (thermogravimetric analysis) of the acrylic resin is a value determined by heat-treating the acrylic resin at a temperature of 110°C for 60 minutes to dry it, then returning it to room temperature and weighing it to 10 to 30 mg as a measurement sample, heating it at a heating rate of 10°C / min in TGA measurement, measuring the weight when it reaches 330°C, and calculating the weight loss rate.

[0034] In the sizing agent for long glass fibers of the present invention, the acrylic resin is preferably contained in the form of an emulsion. Acrylic resin emulsions can be obtained by known methods. Examples of methods for producing acrylic resin emulsions include (i) a method in which water, polymerizable monomers, emulsifiers, polymerization initiators, etc. are mixed together and polymerized; (ii) a pre-emulsion method in which a pre-emulsion in which water, polymerizable monomers, and emulsifiers are pre-mixed is added dropwise; and (iii) a monomer dropping method in which polymerizable monomers, polymerization initiators, etc. are added dropwise to a reaction vessel containing a seed resin.

[0035] The type of emulsifier added to the acrylic resin emulsion is not particularly limited, and examples thereof include polyoxyalkylene alkyl ether surfactants such as polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene alkyl ether, polyoxypropylene alkyl ether, etc. Furthermore, the type of polymerization initiator added to the acrylic resin emulsion is not particularly limited, and examples thereof include persulfates such as sodium persulfate, potassium persulfate, and ammonium persulfate.

[0036] A preferred embodiment of the acrylic resin emulsion used in the present invention is one produced by heating a liquid mixture of water, (meth)acrylic acid and / or a (meth)acrylic acid derivative as a polymerizable monomer, a polyoxyalkylene alkyl ether surfactant as an emulsifier, and a persulfate as a polymerization initiator.

[0037] The mass ratio of component (A) relative to 100 parts by mass of the total mass of all nonvolatile components contained in the sizing agent for long glass fibers of the present invention is, for example, 10 to 80 parts by mass, preferably 10 to 50 parts by mass, and more preferably 15 to 40 parts by mass. In the present invention, the "nonvolatile components" refer to the bone-dry components obtained by heat treatment at 110°C under normal pressure to remove the solvent and the like, and then reaching a constant weight.

[0038] The concentration of component (A) in the sizing agent for long glass fibers of the present invention is, for example, 0.5 to 1.0 mass %, preferably 0.6 to 0.9 mass %, and more preferably 0.7 to 0.9 mass %.

[0039] [(B) Fats and oils] The sizing agent for long glass fibers of the present invention contains an oil (sometimes simply referred to as "component (B)"). The oil mainly functions as a lubricant between the glass fibers, thereby imparting flexibility to the glass yarn and providing it with an excellent effect of suppressing the generation of fluff.

[0040] The type of oil or fat used in the present invention is not particularly limited, but examples thereof include animal oils, vegetable oils, esters of higher fatty acids, hydrocarbon oils, and the like.

[0041] Specific examples of animal oils include beef tallow, beef fat, lard, horse oil, mink oil, fish oil, egg yolk oil, and hardened oils (hydrogenated products) of these oils.

[0042] Specific examples of vegetable oils include soybean oil, rapeseed oil, corn oil, sesame oil, rice germ oil, safflower oil, cottonseed oil, palm oil, almond oil, macadamia nut oil, olive oil, avocado oil, camellia oil, persic oil, carnauba wax, candelilla wax, castor oil, jojoba oil, cacao butter, kukui nut oil, shea butter, evening primrose oil, perilla oil, tea seed oil, palm kernel oil, palm oil, peanut oil, sunflower oil, grape seed oil, meadowhoo oil, and hydrogenated oils thereof.

[0043] Examples of esters of higher fatty acids include esters of higher fatty acids having 12 to 22 carbon atoms and monohydric alcohols having 1 to 22 carbon atoms, preferably esters of higher saturated fatty acids having 16 to 22 carbon atoms and monohydric alcohols having 1 to 10 carbon atoms, and more preferably esters of higher saturated fatty acids having 16 to 22 carbon atoms and monohydric alcohols having 1 to 6 carbon atoms. Specific examples of esters of higher fatty acids include dodecyl stearate, stearyl stearate, and butyl stearate.

[0044] Specific examples of hydrocarbon oils include paraffin wax, liquid paraffin, squalane, petrolatum, ceresin wax, microcrystalline wax, and Fischertropus wax.

[0045] Among these oils and fats, preferred are esters of higher fatty acids and hydrocarbon oils.

[0046] In the sizing agent for long glass fibers of the present invention, one type of oil or fat may be used alone, or two or more types may be used in combination.

[0047] In the sizing agent for long glass fibers of the present invention, the fat or oil is preferably contained in an emulsified state. The emulsification of the fat or oil can be carried out by a known method using an emulsifier or the like.

[0048] The mass ratio of component (B) relative to 100 parts by mass of the total mass of all nonvolatile components contained in the sizing agent for long glass fibers of the present invention is, for example, 20 to 80 parts by mass, preferably 50 to 80 parts by mass, and more preferably 50 to 70 parts by mass.

[0049] In the sizing agent for long glass fibers of the present invention, the ratio of component (B) to component (A) is not particularly limited, but may be, for example, 150 to 300 parts by mass, and preferably 220 to 300 parts by mass, of component (B) per 100 parts by mass of component (A).

[0050] The concentration of component (B) in the sizing agent for long glass fibers of the present invention is, for example, 1.0 to 3.0 mass %, preferably 1.5 to 2.5 mass %, and more preferably 1.8 to 2.2 mass %.

[0051] [(C) Polyoxyethylene alkyl ether and / or cationized cellulose] The sizing agent for long glass fibers of the present invention contains polyoxyethylene alkyl ether and / or cationized cellulose (sometimes simply referred to as "component (C)"). In the present invention, the polyoxyethylene alkyl ether and / or cationized cellulose mainly functions as a lubricating component between the glass fibers, thereby imparting flexibility to the glass yarn and providing excellent fuzz suppression effects, as well as improving heat cleanability at low temperatures of less than 400°C.

[0052] Polyoxyethylene alkyl ether is a compound in which a polyoxyethylene chain and an alkyl group are ether-bonded. The number of carbon atoms in the alkyl group in the polyoxyethylene alkyl ether used in the present invention is, for example, 6 to 30, and preferably 12 to 24. The number of moles of ethylene oxide added in the polyoxyethylene alkyl ether used in the present invention is, for example, 1 to 60, and preferably 3 to 50.

[0053] Specific examples of polyoxyethylene alkyl ethers include polyoxyethylene butyl ether, polyoxyethylene octyl ether, polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, and polyoxyethylene behenyl ether.

[0054] Cationized cellulose refers to cellulose into which positively charged groups have been introduced by modification. The modification is preferably carried out on the hydroxyl groups of the glucose residues of cellulose, and such modification can introduce positively charged groups, for example, via ester bonds or ether bonds. Examples of cationized cellulose include cellulose into which a group that exhibits an onium ion (positive charge), such as an ammonium ion, phosphonium ion, or sulfonium ion, has been introduced by modification in water, and preferred is cellulose into which a group that exhibits an ammonium ion in water has been introduced. The cationized cellulose may form a salt with a negatively charged atom or molecule. Furthermore, the cationized cellulose may be any cellulose that exhibits solubility in the solvent of the present invention, and there are no particular limitations on the degree of modification, molecular weight, etc.

[0055] A suitable example of the cationized cellulose used in the present invention is a hydroxyalkyl cellulose having a quaternary ammonium group. Specific examples of hydroxyalkyl cellulose having a quaternary ammonium group include O-(2-hydroxy-3-(trimethylammonio)propyl)hydroxyethyl cellulose chloride, O-(2-hydroxy-3-(lauryldimethylammonio)propyl)hydroxyethyl cellulose chloride, and hydroxyethyl cellulose dimethyl diallyl ammonium chloride. Among these, O-(2-hydroxy-3-(trimethylammonio)propyl)hydroxyethyl cellulose chloride is preferred.

[0056] The long glass fiber sizing agent of the present invention may contain one of polyoxyethylene alkyl ether and cationized cellulose alone, or may contain two or more of them in combination.

[0057] Among polyoxyethylene alkyl ethers and cationized cellulose, polyoxyethylene alkyl ethers are preferred from the viewpoint of further improving the effect of suppressing the generation of fluff and the heat cleanability under low temperature conditions.

[0058] When polyoxyethylene alkyl ether is contained as component (C), the mass ratio of the polyoxyethylene alkyl ether relative to 100 parts by mass of the total mass of all non-volatile components contained in the sizing agent for long glass fibers of the present invention is, for example, 1 to 15 parts by mass, preferably 1 to 10 parts by mass, and more preferably 2 to 6 parts by mass.

[0059] When polyoxyethylene alkyl ether is contained as component (C), the ratio of polyoxyethylene alkyl ether to component (A) is, for example, 10 to 50 parts by mass, preferably 10 to 20 parts by mass, of polyoxyethylene alkyl ether per 100 parts by mass of component (A).

[0060] Furthermore, when polyoxyethylene alkyl ether is contained as component (C), the concentration of polyoxyethylene alkyl ether in the sizing agent for long glass fibers of the present invention is, for example, 0.1 to 0.4 mass%, preferably 0.1 to 0.3 mass%, and more preferably 0.1 to 0.2 mass%.

[0061] When cationized cellulose is contained as component (C), the mass ratio of the cationized cellulose relative to 100 parts by mass of the total mass of all non-volatile components contained in the sizing agent for long glass fibers of the present invention is, for example, 0.1 to 2 parts by mass, preferably 0.1 to 1 part by mass, and more preferably 0.2 to 0.8 parts by mass.

[0062] When cationized cellulose is contained as component (C), the ratio of cationized cellulose to component (A) is, for example, 2 to 8 parts by mass, and preferably 2 to 5 parts by mass, of cationized cellulose per 100 parts by mass of component (A).

[0063] When cationized cellulose is contained as component (C), the concentration of the cationized cellulose in the sizing agent for long glass fibers of the present invention is, for example, 0.01 to 0.05% by mass, preferably 0.01 to 0.04% by mass, and more preferably 0.01 to 0.03% by mass.

[0064] [Total amount of components (A) to (C)] The ratio of the total amount of components (A) to (C) (the total content of components (A) to (C)) to 100 parts by mass of the total mass of all nonvolatile components contained in the sizing agent for long glass fibers of the present invention is, for example, 50 parts by mass or more, preferably 60 parts by mass or more. The upper limit of this ratio is, for example, 100 parts by mass, 99 parts by mass, 95 parts by mass, or 80 parts by mass.

[0065] [Non-volatile components other than components (A) to (C)] In addition to components (A) to (C), the glass fiber sizing agent of the present invention may contain other nonvolatile components as long as the effects of the present invention are achieved.

[0066] Examples of non-volatile components that can be incorporated into the glass fiber sizing agent of the present invention include softener components. Examples of softener components include polyamide derivatives, fatty acid amide derivatives, alkylamide derivatives, amino-modified silicone derivatives, and polyamine derivatives. Among these softener components, alkylamide derivatives are preferred.

[0067] Examples of alkylamide derivatives include compounds represented by the following general formula (1): 1 represents a linear or branched alkyl or alkenyl group. 1The number of carbon atoms in the alkyl group or alkenyl group is, for example, 7 to 23, preferably 10 to 18, and more preferably 12 to 16. In addition, in the general formula (1), R 2 represents a methyl group, an ethyl group, a hydroxymethyl group, or a hydroxyethyl group. [ka]

[0068] When a softener component is contained in the glass fiber sizing agent of the present invention, the mass ratio of the softener component to 100 parts by mass of the total mass of all non-volatile components contained in the long glass fiber sizing agent of the present invention is, for example, 1 to 12 parts by mass, preferably 3 to 6 parts by mass.

[0069] Furthermore, when a softening agent component is contained in the glass fiber sizing agent of the present invention, the concentration of the softening agent component in the long glass fiber sizing agent of the present invention is, for example, 0.03 to 0.3 mass%, preferably 0.05 to 0.2 mass%, and more preferably 0.1 to 0.2 mass%.

[0070] Another example of a non-volatile component that can be blended into the glass fiber sizing agent of the present invention is polyethylene glycol, which can further improve the effect of suppressing fluffing and the heat cleaning ability at low temperatures.

[0071] The average molecular weight of the polyethylene glycol used in the present invention is not particularly limited, but may be, for example, 100 to 1000, preferably 200 to 500, as a weight average molecular weight calculated as a polystyrene equivalent by the GPC method.

[0072] When polyethylene glycol is contained in the glass fiber sizing agent of the present invention, the mass ratio of polyethylene glycol to 100 parts by mass of the total mass of all non-volatile components contained in the long glass fiber sizing agent of the present invention is, for example, 15 to 25 parts by mass.

[0073] When polyethylene glycol is contained in the glass fiber sizing agent of the present invention, the concentration of polyethylene glycol in the long glass fiber sizing agent of the present invention is, for example, 0.5 to 0.8 mass%, preferably 0.6 to 0.8 mass%, and more preferably 0.7 to 0.8 mass%.

[0074] Furthermore, the sizing agent for long glass fibers of the present invention preferably contains an emulsifier in addition to the nonvolatile components described above in order to emulsify the acrylic resin and oil. The concentration of the emulsifier in the sizing agent for long glass fibers of the present invention may be appropriately set depending on the type of emulsifier used within a range that allows the acrylic resin and oil to be emulsified.

[0075] When the sizing agent for long glass fibers of the present invention contains non-volatile components other than the components (A) to (C), the ratio of the total amount of non-volatile components other than the components (A) to (C) (total amount of non-volatile components other than the components (A) to (C)) relative to 100 parts by mass of the total mass of all non-volatile components contained in the sizing agent for long glass fibers of the present invention is, for example, 40 parts by mass or less, preferably 10 to 40 parts by mass, and more preferably 20 to 40 parts by mass.

[0076] [Total concentration of non-volatile components] In the sizing agent for long glass fibers of the present invention, the total concentration of nonvolatile components (total concentration of components (A) to (C) and other nonvolatile components) is, for example, 2.5 to 4.5 mass%, preferably 3.0 to 4.0 mass%.

[0077] [Aqueous solvent (volatile components)] The sizing agent for long glass fibers of the present invention contains an aqueous solvent (volatile component) as a base. The type of aqueous medium is not particularly limited, but examples include water, water-soluble organic solvents, and mixtures thereof. Examples of water-soluble organic solvents include alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol, ethyl carbitol, ethyl cellosolve, and butyl cellosolve, and polar solvents such as N-methylpyrrolidone.

[0078] The concentration of the aqueous solvent in the sizing agent for long glass fibers of the present invention may be any concentration as long as it accounts for the remainder excluding nonvolatile components.

[0079] [Manufacturing method] The sizing agent for long glass fibers of the present invention can be obtained by mixing predetermined amounts of components (A) to (C), other non-volatile components that are blended as necessary, and an aqueous solvent. Alternatively, an acrylic resin emulsion as component (A) and an emulsified oil as component (B) can be prepared in advance, and the acrylic resin emulsion and the emulsified oil can be mixed with other components to easily obtain an emulsified sizing agent for long glass fibers.

[0080] [How to use] The sizing agent for long glass fibers of the present invention is used to prepare a glass yarn (glass fiber bundle) by bundling long glass fibers. The long glass fibers treated with the sizing agent for long glass fibers of the present invention are in a state in which their surfaces are coated with a film of nonvolatile components.

[0081] The type of long glass fibers to be treated with the long glass fiber sizing agent of the present invention is not particularly limited, and examples include E-glass, T-glass, S-glass, D-glass, NE-glass, C-glass, H-glass, ARG-glass, and quartz glass. Among these, E-glass is preferred from the viewpoint of further improving heat cleaning properties under low-temperature conditions. In the present invention, E-glass specifically refers to a glass material made of a glass composition containing 52 to 56 mass% of SiO2, 12 to 16 mass% of Al2O3, 20 to 25 mass% of CaO+MgO, and 5 to 10 mass% of B2O3.

[0082] Another suitable example of long glass fibers to be treated with the long glass fiber sizing agent of the present invention is long glass fibers having low dielectric properties. An example of a glass composition constituting long glass fibers having low dielectric properties is a glass composition containing 45 to 60 mass% SiO2, 15 to 35 mass% B2O3, and 10 to 20 mass% Al2O3. A suitable example of long glass fibers having low dielectric properties is a glass composition having a dielectric constant of less than 5.0 at a frequency of 1 MHz, more specifically, a glass composition containing 50 to 56 mass% SiO2, 20 to 30 mass% B2O3, and 10 to 20 mass% Al2O3. In this specification, the term "dielectric constant" refers to the relative dielectric constant, which is the ratio to the dielectric constant in a vacuum. In this specification, the "dielectric constant at a frequency of 1 MHz" is a value measured in accordance with ASTM D150-87 at a measurement temperature of 20°C.

[0083] The fiber diameter of the long glass fibers to be treated with the long glass fiber sizing agent of the present invention is not particularly limited, but from the viewpoint of more effectively exhibiting the effect of suppressing the generation of fluff and heat cleaning properties under low temperature conditions, it is preferably 2 to 5 μm, more preferably 2 to 4.5 μm.

[0084] The count of the long glass fibers to be treated with the long glass fiber sizing agent of the present invention is not particularly limited, but from the viewpoint of more effectively exhibiting the effect of suppressing the generation of fluff and heat cleaning properties under low temperature conditions, it is preferably 1 to 12 tex, more preferably 1 to 5 tex, and particularly preferably 1 to 3 tex.

[0085] The number of filaments of long glass fibers to be bundled into one glass yarn using the sizing agent for long glass fibers of the present invention is not particularly limited, but may be, for example, 40 to 400, preferably 40 to 200, and more preferably 40 to 100.

[0086] To prepare a glass yarn by treating long glass fibers with the long glass fiber sizing agent of the present invention, the long glass fibers are coated with the sizing agent of the present invention, bundled, and then dried. To apply the sizing agent of the present invention to the long glass fibers, for example, a roller-type or belt-type applicator, a spray, or the like may be used. To bundle the long glass fibers coated with the sizing agent of the present invention, a known bundler may be used. Drying after bundling may be carried out, for example, at a temperature ranging from room temperature to 150°C. By applying the sizing agent of the present invention to the long glass fibers, bundled, and then drying, volatile components such as the aqueous solvent are removed, and a glass yarn is obtained in which a film of the nonvolatile components contained in the sizing agent of the present invention is formed on the surfaces of the long glass fibers. The glass yarn thus obtained can be twisted, if necessary, with a twisting machine and used as a raw material for glass cloth.

[0087] The amount of the sizing agent for long glass fibers of the present invention to be attached to the long glass fibers to be treated may be appropriately set within a range in which the effect of suppressing fuzz generation is effectively exhibited, for example, within a range in which the ignition loss of the bundled glass yarn is 0.3 to 2.0 mass%, preferably 0.3 to 1.2 mass%. The ignition loss of the glass yarn substantially corresponds to the amount of nonvolatile components attached in the sizing agent for long glass fibers of the present invention, and is a value measured according to the method specified in "7.3.2 Ignition Loss" of "General Test Methods for Glass Fibers" of JIS R 3420 2013.

[0088] 2. Glass yarn The glass yarn of the present invention is characterized by comprising a continuous glass fiber having a coating formed on its surface, the coating containing (A) an acrylic resin, (B) an oil or fat, and (C) a cationized cellulose and / or a polyoxyethylene alkyl ether.

[0089] The glass yarn of the present invention can be obtained by treating long glass fibers with the aforementioned sizing agent for long glass fibers. The type, fiber diameter, and count of the long glass fibers used in the glass yarn of the present invention are as described above in the section "1. Sizing Agent for Long Glass Fibers." The amount of the coating formed on the long glass fibers is the same as the ignition loss described above in the section "1. Sizing Agent for Long Glass Fibers." The types of (A) acrylic resin, (B) oil, and (C) cationized cellulose and / or polyoxyethylene alkyl ether contained in the coating formed on the long glass fibers, the types of other nonvolatile components that may be contained in the coating, and the composition of the coating are also the same as the types and compositions of the nonvolatile components described above in the section "1. Sizing Agent for Long Glass Fibers."

[0090] 3. Glass cloth The glass cloth of the present invention can be obtained by weaving the glass yarn as a raw material yarn and then subjecting the glass yarn to a heat cleaning treatment. Since the glass cloth of the present invention is produced using a glass yarn on which a coating containing (A) an acrylic resin, (B) a fat or oil, and (C) a cationized cellulose and / or a polyoxyethylene alkyl ether is formed, a low-temperature condition of less than 400°C can be employed in the heat cleaning treatment during production. As a result, a decrease in the tensile strength and other properties of the glass cloth due to the heat cleaning treatment can be suppressed, and the glass cloth can have excellent tensile strength.

[0091] The weave of the glass cloth of the present invention is not particularly limited, and examples thereof include plain weave, satin weave, sash weave, leno weave, imitation weave, twill weave, etc. The weave density of the glass cloth of the present invention is not particularly limited, and examples thereof include about 10 to 150 threads / 25 mm and about 50 to 130 threads / 25 mm for both warp and weft.

[0092] The thickness of the glass cloth of the present invention is not particularly limited, but from the viewpoint of more effectively suppressing the decrease in the tensile strength, etc. of the glass cloth due to the heat cleaning treatment and providing excellent tensile strength, the thickness is about 8 to 20 μm, preferably about 8 to 15 μm, and more preferably about 8 to 13 μm.

[0093] The mass of the glass cloth of the present invention is not particularly limited, but from the viewpoint of more effectively suppressing the decrease in the tensile strength of the glass cloth due to the heat cleaning treatment and providing excellent tensile strength, it is preferably 3 to 30 g / m 2 Approximately, preferably 3 to 20 g / m 2 More preferably, 7 to 14 g / m 2 The degree of

[0094] Furthermore, glass cloth obtained using glass yarns treated with a starch-based sizing agent requires a heat cleaning treatment at high temperatures of 400°C or higher, which inevitably reduces the tensile strength of the glass yarns constituting the glass cloth. For example, when heat cleaning is performed at 400°C for 60 hours, the tensile strength of the glass yarns decreases to less than half of that before the heat cleaning treatment. In contrast, the glass cloth of the present invention is produced using the glass yarns, and therefore can be heated at low temperatures of less than 400°C. As a result, the glass yarns constituting the glass cloth have excellent tensile strength. In view of the effects of the present invention, a preferred embodiment of the glass cloth of the present invention is one in which the glass yarns constituting the glass cloth have a high tensile strength, specifically, a tensile strength of 0.45 N / tex or higher, preferably 0.45 to 0.60 N / tex, and more preferably 0.50 to 0.60 N / tex. Glass cloth containing glass yarns with such tensile strength can be suitably obtained by heat cleaning at temperatures of 280 to 330°C.

[0095] The ignition loss of the glass cloth of the present invention is, for example, 0.10% by mass or less, preferably 0.04 to 0.10% by mass. The ignition loss of the glass cloth substantially corresponds to the amount of nonvolatile organic components attached to the glass cloth, and is a value measured according to the method specified in "7.3.2 Ignition loss" of "General test methods for glass fibers" of JIS R 3420 2013.

[0096] In addition, one preferred embodiment of the glass cloth of the present invention is one in which the glass material is E-glass or a glass composition having a dielectric constant of less than 5.0 at a frequency of 1 MHz, the glass yarn constituting the glass cloth has a tensile strength of 0.50 N / tex or more, preferably 0.45 to 0.60 N / tex, and more preferably 0.50 to 0.60 N / tex, and the loss on ignition is 0.10 mass% or less, preferably 0.04 to 0.10 mass%.

[0097] The use of the glass cloth of the present invention is not particularly limited, and it can be used in any use to which glass cloth has conventionally been applied. Furthermore, glass cloth for printed wiring boards (glass cloth used as a core material for printed wiring boards) is required to be thin in thickness in order to accommodate high-density mounting and lighter, thinner, shorter, and smaller sizes. However, conventional techniques have the drawback that thin glass cloths are prone to fluffing. In contrast, the glass cloth of the present invention can suppress fluffing even when thin, and can fully satisfy the required properties of glass cloth for printed wiring boards. In view of the effects of the present invention, a suitable example of the use of the glass cloth of the present invention is glass cloth for printed wiring boards, particularly glass cloth for thin printed wiring boards. The thickness of the thin glass cloth is, for example, 8 to 20 μm.

[0098] The glass cloth of the present invention can be obtained by weaving the glass yarn as a raw material yarn and then subjecting the weaved yarn to a heat cleaning treatment. Specifically, the glass cloth of the present invention can be obtained through the following steps A and B. Step A: A step of weaving a greige cloth using the glass yarn as a warp and a weft. Step B: A step of subjecting the green cloth to heat cleaning treatment.

[0099] In the step A, the glass yarns are used as warp and weft threads, and the glass cloth may be woven by a known method depending on the weave structure, weaving density, etc. of the glass cloth.

[0100] The warp yarns used in the step A may be further treated with a secondary sizing agent. The composition of the secondary sizing agent to be used is not particularly limited, but preferably, the secondary sizing agent has the same composition as the sizing agent for long glass fibers.

[0101] The temperature conditions for the heat cleaning treatment in the step B are not particularly limited and may be appropriately set so that the ignition loss of the resulting glass cloth falls within the above-mentioned range, for example, from 250 to 600° C. As described above, the glass cloth of the present invention can be subjected to heat cleaning treatment at a low temperature of less than 400° C., and as a result, a decrease in the tensile strength, etc. of the glass yarn due to the heat cleaning treatment can be suppressed. Therefore, from the viewpoint of suppressing a decrease in tensile strength, the conditions for the heat cleaning treatment are preferably less than 400° C., more preferably 280 to 390° C., even more preferably 280 to 330° C., and particularly preferably 290 to 330° C.

[0102] The time for the heat cleaning treatment in the step B may be appropriately set so that the ignition loss of the glass cloth obtained falls within the above-mentioned range depending on the temperature conditions employed. For example, when the glass cloth is made into a roll product (a product in which the glass cloth is wound around a core) and the roll product is subjected to the heat cleaning treatment as is, the time may be 48 to 96 hours, preferably 48 to 72 hours, and more preferably 48 to 60 hours.

[0103] Furthermore, the method for producing a glass cloth for a printed wiring board of the present invention may, if necessary, include other treatment steps in addition to the steps A and B. Examples of such treatment steps include a fiber-opening treatment step for widening the glass yarns constituting the glass cloth, and a surface treatment step using a silane coupling agent. [Example]

[0104] The present invention will be described in detail below with reference to examples, but the present invention is not limited to the following examples.

[0105] 1. Test Method 1-1. Ignition loss of glass yarn and glass cloth The ignition losses of the glass yarn and glass cloth were measured and calculated according to the method specified in "7.3.2 Ignition Loss" of "General Test Methods for Glass Fibers" in JIS R 3420 2013. For the glass yarns of Examples 4 to 6 and Comparative Example 5, the ignition losses (ignition losses after heat treatment condition 1 (330°C)) were also measured for those that had been heat treated under the following heat treatment condition 1 and returned to room temperature. Heat treatment condition 1: Hang in a hot air furnace at 330°C for 60 minutes

[0106] 1-2. Single fiber diameter of long glass fiber (μm) The single fiber diameter of the long glass fiber was measured and calculated according to the method specified in "7.6 Single Fiber Diameter" of "General Test Methods for Glass Fibers" of JIS R 3420 2013, Method B (cross section method).

[0107] 1-3.Glass yarn count (tex) The count of the glass yarn was measured and calculated according to the method specified in "7.1 Count" of "General Test Methods for Glass Fibers" of JIS R 3420 2013.

[0108] 1-4. Glass yarn fluff (pieces / 100m) The obtained glass yarn was unwound at a speed of 100 m / min and passed through a tension bar, after which the number of fluffs was counted with a sensor. The number of fluffs per 100 m (number / 100 m) was calculated by counting for 1 km.

[0109] 1-5.Glass cloth weave density The weave density of the warp and weft yarns was measured and calculated according to the method specified in "7.9 Density (weave density)" of "General test methods for glass fibers" in JIS R 3420 2013.

[0110] 1-6. Thickness of glass cloth The thickness of the glass cloth was measured and calculated according to the method specified in "7.10 Thickness of cloth and mat" of "General test methods for glass fibers" of JIS R 3420 2013.

[0111] 1-7. Mass of glass cloth The mass of the glass cloth was measured and calculated according to the method specified in [7.2 Mass of cloth and mat (mass)] of JIS R 3420 2013 "General test method for glass fibers."

[0112] 1-8. Tensile strength of glass yarn (N / tex) Glass yarn was extracted from the grey fabric before heat cleaning. The glass yarn was heat treated under the following heat treatment conditions 1 or 2 and returned to room temperature, and then used as a sample for a tensile test. The tensile test was performed in accordance with the method specified in "7.4 Tensile Strength" of "General Test Methods for Glass Fibers" of JIS R 3420 2013, using a tensile tester, Model 2100 manufactured by Intesco Co., Ltd., with a grip spacing of 250 mm, a test speed of 250 mm / min, and a number of 10 strands. The average tensile strength (N) was calculated, and this was divided by the count of the glass yarn to calculate the tensile strength (N / tex). The heat treatment in the hot air furnace was carried out under the following two conditions. Heat treatment condition 1: Hang in a hot air furnace at 330°C for 60 minutes Heat treatment condition 2: Hang in a hot air furnace at 400°C for 60 minutes

[0113] 1-9. Heat cleaning properties of glass cloth Poor heat cleanability can be evaluated by the color difference before and after heat cleaning, since nonvolatile organic components remain after the heat cleaning process and are manifested as color. Therefore, we performed a color test on glass cloth before and after heat cleaning (330°C, 60 minutes). For the color test, we used a Konica Minolta CR300 colorimeter to calculate the color difference (ΔE) using the CIE 1976 (L*a*b*) color difference formula. A color difference (ΔE) of 0–0.1 is considered indistinguishable by the naked eye; 0.2–0.4 is discernible by someone familiar with color testing; 0.8–1.5 is often considered a quality control standard; and 3.0 or greater is considered a level at which color differences are likely to lead to complaints due to color inaccuracies. Therefore, a color difference (ΔE) of 1.5 or less can be considered heat cleanable.

[0114] 2. Materials used in preparing the sizing agent for long glass fibers In the examples and comparative examples, the following components were used as blending components in the sizing agent for long glass fibers. (1) Acrylic resin emulsion: GF-6, manufactured by GOO Chemical Co., Ltd. [nonvolatile components: 25% by mass; weight loss at 330°C in TGA (thermogravimetric analysis): 98% by mass; weight-average molecular weight of acrylic resin: 300,000; average particle size (median diameter) of acrylic resin: 150 nm; produced by heating a liquid mixture containing, in addition to acrylic resin, water, 2-ethylhexyl methacrylate and isobutyl methacrylate as polymerizable monomers, polyoxyethylene polyoxypropylene alkyl ether (trade name: Nonion HT-501, NOF Corporation), a polyoxyalkylene alkyl ether surfactant, as an emulsifier, and ammonium persulfate as a polymerization initiator] (2) Oil emulsion A: Matsumoto Yushi Pharmaceutical Co., Ltd. product name KP-2708 (main component is butyl stearate emulsion, oil content is 50% by mass) (3) Oil emulsion B: Yoshimura Oil Chemical Co., Ltd., product name Smoother SW45 (paraffin wax emulsion, paraffin wax content 30% by mass) (4) Cationic cellulose: O-(2-hydroxy-3-(trimethylammonio)propyl)hydroxyethyl cellulose chloride (cationic cellulose: 98% by mass) (5) Polyoxyethylene alkyl ether: Matsumoto Yushi Pharmaceutical Co., Ltd., trade name Marpoterone LE (polyoxyethylene alkyl ether: 30% by mass) (6) N,N,N,N-tetraalkyl quaternary ammonium salt: trade name Anstex SAG-25 (N,N,N,N-tetraalkyl quaternary ammonium salt: 25% by mass), manufactured by Toho Chemical Industry Co., Ltd. (7) Polyoxyethylene alkyl ester: Product name: Neulan O-6 (polyoxyethylene alkyl ester: 30% by mass), manufactured by Ipposha Oil & Fat Industries Co., Ltd. (8) Alkylamide derivative: Matsumoto Yushi Pharmaceutical Co., Ltd., trade name KP-914 (alkylamide derivative: 30% by mass) (9) Polyethylene glycol (average molecular weight 300): manufactured by Toho Chemical Industry Co., Ltd., trade name PEG-300 (10) Polyethylene glycol (average molecular weight 400): manufactured by Toho Chemical Industry Co., Ltd., trade name PEG-400

[0115] 3. Manufacturing of sizing agents for long glass fibers, glass yarn and glass cloth [Example 1] (1) Manufacturing of sizing agents for long glass fibers The components were mixed to obtain the following composition to obtain a sizing agent for long glass fibers. Note that the parts by mass shown below are values ​​converted to the amount of nonvolatile components except for "water" and "total," and the "total" is the total value of volatile and nonvolatile components. Acrylic resin emulsion: 75 parts by weight Fat emulsion A: 150 parts by mass Paraffin wax emulsion: 50 parts by mass Cationic cellulose: 2 parts by mass Alkylamide derivative: 15 parts by mass Water: 9708 parts by mass Total: 10000 parts by mass

[0116] The ratio of the mass (g) of all nonvolatile components to the mass of the sizing agent for long glass fibers was 2.92 mass %. The composition ratio of the nonvolatile components is shown in Table 1.

[0117] (2) Glass yarn manufacturing The sizing agent for long glass fibers was applied using a roll applicator to a plurality of long glass fibers (E glass, filament diameter 4.1 μm) spun from a spinning furnace, and the long glass fibers were bundled into a single bundle (strand). This strand was then wound around a tube without twisting to obtain a cake. The obtained cake was then dried at room temperature. The strand was unwound from the dried cake and wound around a bobbin while being twisted to obtain a glass yarn. The obtained glass yarn had a filament count of 50, a twist count of 0.5Z, a count of 1.68 tex, and an ignition loss of 0.25% by mass.

[0118] (3) Glass cloth manufacturing The obtained glass yarn was used as the weft. A secondary sizing agent having the same composition as the long glass fiber sizing agent used in the production of the glass yarn was applied to the obtained glass yarn by a conventional method, and the yarn was sized and beamed. The resulting warp beam was used as the warp. The warp and weft yarns were set in an air jet loom and woven in a plain weave with a warp density of 95 / 25 mm and a weft density of 95 / 25 mm. After weaving, the fabric was subjected to a water jet treatment to open the fibers, resulting in a greige cloth. The ignition loss of the obtained greige cloth was 1.2% by mass, the thickness was 18 μm, and the mass was 12.8 g / m. 2 It was.

[0119] The obtained greige cloth was cut into A4 size pieces and subjected to heat cleaning treatment by hanging it in a hot air oven at 330°C for 60 minutes to obtain a glass cloth. The obtained glass cloth had an ignition loss of 0.07% by mass, a thickness of 15 μm, and a mass of 12.5 g / m. 2 It was.

[0120] [Example 2] (1) Manufacturing of sizing agents for long glass fibers The components were mixed to obtain the following composition to obtain a sizing agent for long glass fibers. Note that the parts by mass shown below are values ​​converted to the amount of nonvolatile components except for "water" and "total," and the "total" is the total value of volatile and nonvolatile components. Acrylic resin emulsion: 75 parts by weight Fat emulsion A: 150 parts by mass Paraffin wax emulsion: 50 parts by mass Cationic cellulose: 2 parts by mass Alkylamide derivative: 3 parts by mass Water: 9270 parts by mass Total: 10000 parts by mass

[0121] The ratio of the mass (g) of all non-volatile components to the mass of the sizing agent for long glass fibers was 2.8 mass %. The composition ratio of the non-volatile components is shown in Table 1.

[0122] (2) Glass yarn manufacturing Except for using the sizing agent for long glass fibers, a glass yarn was obtained under the same conditions as in Example 1. The obtained glass yarn had 50 filaments, a twist of 0.5Z, a count of 1.68 tex, and an ignition loss of 0.22% by mass.

[0123] (3) Glass cloth manufacturing A greige cloth and a glass cloth were produced under the same conditions as in Example 1, except that the obtained glass yarn was used and that a secondary sizing agent for the warp yarns had the same composition as the bundling agent for long glass fibers (Example 2).

[0124] The ignition loss of the obtained greige cloth was 1.2% by mass, the thickness was 18 μm, and the mass was 12.8 g / m 2 The ignition loss of the obtained glass cloth was 0.07% by mass, the thickness was 15 μm, and the mass was 12.5 g / m 2 It was.

[0125] [Example 3] (1) Manufacturing of sizing agents for long glass fibers The components were mixed to obtain the following composition to obtain a sizing agent for long glass fibers. Note that the parts by mass shown below are values ​​converted to the amount of nonvolatile components except for "water" and "total," and the "total" is the total value of volatile and nonvolatile components. Acrylic resin emulsion: 75 parts by weight Fat emulsion A: 150 parts by mass Fat emulsion B: 50 parts by mass Polyoxyethylene alkyl ether: 12 parts by mass Alkylamide derivative: 30 parts by mass Water: 9683 parts by mass Total: 10000 parts by mass

[0126] The ratio of the mass (g) of all nonvolatile components to the mass of the sizing agent for long glass fibers was 3.17 mass %. The composition ratio of the nonvolatile components is shown in Table 1.

[0127] (2) Glass yarn manufacturing Except for using the sizing agent for long glass fibers, a glass yarn was obtained under the same conditions as in Example 1. The obtained glass yarn had 50 filaments, a twist of 0.5Z, a count of 1.68 tex, and an ignition loss of 0.38% by mass.

[0128] (3) Glass cloth manufacturing A greige cloth and a glass cloth were produced under the same conditions as in Example 1, except that the obtained glass yarn was used and that a secondary sizing agent for the warp yarns had the same composition as the sizing agent for long glass fibers (Example 3).

[0129] The ignition loss of the obtained greige cloth was 1.0% by mass, the thickness was 18 μm, and the mass was 12.8 g / m 2 The ignition loss of the obtained glass cloth was 0.08% by mass, the thickness was 15 μm, and the mass was 12.5 g / m 2 It was.

[0130] [Example 4] (1) Manufacturing of sizing agents for long glass fibers The components were mixed to obtain the following composition to obtain a sizing agent for long glass fibers. Note that the parts by mass shown below are values ​​converted to the amount of nonvolatile components except for "water" and "total," and the "total" is the total value of volatile and nonvolatile components. Acrylic resin emulsion: 75 parts by weight Fat emulsion A: 150 parts by mass Fat emulsion B: 50 parts by mass Polyoxyethylene alkyl ether: 12 parts by mass Alkylamide derivative: 15 parts by mass Water: 9698 parts by mass Total: 10000 parts by mass

[0131] The ratio of the mass (g) of all non-volatile components to the mass of the sizing agent for long glass fibers was 3.02 mass %. The composition ratio of the non-volatile components is shown in Table 1.

[0132] (2) Glass yarn manufacturing A glass yarn was obtained under the same conditions as in Example 1, except that the sizing agent for long glass fibers was used. The obtained glass yarn had 50 filaments, a twist of 0.5Z, a yarn count of 1.68 tex, and an ignition loss of 0.44% by mass. The ignition loss of the glass yarn after heat treatment under heat treatment condition 1 was 0.04% by mass.

[0133] (3) Glass cloth manufacturing A greige cloth and a glass cloth were produced under the same conditions as in Example 1, except that the obtained glass yarn was used and that a secondary sizing agent for the warp yarns had the same composition as the bundling agent for long glass fibers (Example 4).

[0134] The ignition loss of the obtained greige cloth was 1.0% by mass, the thickness was 18 μm, and the mass was 12.8 g / m 2 The ignition loss of the obtained glass cloth was 0.06% by mass, the thickness was 15 μm, and the mass was 12.5 g / m 2 It was.

[0135] [Example 5] (1) Manufacturing of sizing agents for long glass fibers The components were mixed to obtain the following composition to obtain a sizing agent for long glass fibers. Note that the parts by mass shown below are values ​​converted to the amount of nonvolatile components except for "water" and "total," and the "total" is the total value of volatile and nonvolatile components. Acrylic resin emulsion: 75 parts by weight Fat emulsion A: 150 parts by mass Fat emulsion B: 50 parts by mass Polyoxyethylene alkyl ether: 12 parts by mass Alkylamide derivative: 15 parts by mass Polyethylene glycol (average molecular weight 300): 75 parts by mass Water: 9623 parts by mass Total: 10000 parts by mass

[0136] The ratio of the mass (g) of all non-volatile components to the mass of the sizing agent for long glass fibers was 3.77 mass %. The composition ratio of the non-volatile components is shown in Table 1.

[0137] (2) Glass yarn manufacturing A glass yarn was obtained under the same conditions as in Example 1, except that the sizing agent for long glass fibers was used. The obtained glass yarn had 50 filaments, a twist of 0.5Z, a yarn count of 1.68 tex, and an ignition loss of 0.49% by mass. The ignition loss of the glass yarn after heat treatment under heat treatment condition 1 was 0.04% by mass.

[0138] (3) Glass cloth manufacturing A greige cloth and a glass cloth were produced under the same conditions as in Example 1, except that the obtained glass yarn was used and that a secondary sizing agent for the warp yarns had the same composition as the sizing agent for long glass fibers (Example 5).

[0139] The ignition loss of the obtained greige cloth was 0.9% by mass, the thickness was 18 μm, and the mass was 12.8 g / m 2 The ignition loss of the obtained glass cloth was 0.09% by mass and the thickness was 15 μm. m, mass is 12.5 g / m2 It was.

[0140] [Example 6] (1) Manufacturing of sizing agents for long glass fibers The components were mixed to obtain the following composition to obtain a sizing agent for long glass fibers. Note that the parts by mass shown below are values ​​converted to the amount of nonvolatile components except for "water" and "total," and the "total" is the total value of volatile and nonvolatile components. Acrylic resin emulsion: 75 parts by weight Fat emulsion A: 150 parts by mass Fat emulsion B: 50 parts by mass Polyoxyethylene alkyl ether: 12 parts by mass Alkylamide derivative: 15 parts by mass Polyethylene glycol (average molecular weight 400): 75 parts by mass Water: 9623 parts by mass Total: 10000 parts by mass

[0141] The ratio of the mass (g) of all non-volatile components to the mass of the sizing agent for long glass fibers was 3.77 mass %. The composition ratio of the non-volatile components is shown in Table 1.

[0142] (2) Glass yarn manufacturing A glass yarn was obtained under the same conditions as in Example 1, except that the sizing agent for long glass fibers was used. The obtained glass yarn had 50 filaments, a twist of 0.5Z, a yarn count of 1.68 tex, and an ignition loss of 0.40% by mass. The ignition loss of the glass yarn after heat treatment under heat treatment condition 1 was 0.04% by mass.

[0143] (3) Glass cloth manufacturing A greige cloth and a glass cloth were produced under the same conditions as in Example 1, except that the obtained glass yarn was used and that a secondary sizing agent for the warp yarns had the same composition as the sizing agent for long glass fibers (Example 6).

[0144] The ignition loss of the obtained greige cloth was 1.0% by mass, the thickness was 18 μm, and the mass was 12.8 g / m2 The ignition loss of the obtained glass cloth was 0.09% by mass, the thickness was 15 μm, and the mass was 12.5 g / m 2 It was.

[0145] [Comparative Example 1] (1) Manufacturing of sizing agents for long glass fibers The components were mixed to obtain the following composition to obtain a sizing agent for long glass fibers. Note that the parts by mass shown below are values ​​converted to the amount of nonvolatile components except for "water" and "total," and the "total" is the total value of volatile and nonvolatile components. Acrylic resin emulsion: 75 parts by weight Fat emulsion A: 150 parts by mass Fat emulsion B: 50 parts by mass N,N,N,N-tetraalkyl quaternary ammonium salt: 12 parts by mass Alkylamide derivative: 30 parts by mass Water: 9683 parts by mass Total: 10000 parts by mass

[0146] The ratio of the mass (g) of all nonvolatile components to the mass of the sizing agent for long glass fibers was 3.17 mass %. The composition ratio of the nonvolatile components is shown in Table 1.

[0147] (2) Glass yarn manufacturing Except for using the sizing agent for long glass fibers, a glass yarn was obtained under the same conditions as in Example 1. The obtained glass yarn had 50 filaments, a twist of 0.5Z, a count of 1.68 tex, and an ignition loss of 0.35% by mass.

[0148] (3) Glass cloth manufacturing A greige cloth and a glass cloth were produced under the same conditions as in Example 1, except that the obtained glass yarn was used and that a secondary sizing agent for warp yarns was used that had the same composition as the long glass fiber sizing agent (Comparative Example 1).

[0149] The ignition loss of the obtained grey cloth was 1.1% by mass, the thickness was 18 μm, and the mass was 12.8 g / m 2The ignition loss of the obtained glass cloth was 0.13% by mass, the thickness was 15 μm, and the mass was 12.5 g / m 2 It was.

[0150] Comparative Example 2 (1) Manufacturing of sizing agents for long glass fibers The components were mixed to obtain the following composition to obtain a sizing agent for long glass fibers. Note that the parts by mass shown below are values ​​converted to the amount of nonvolatile components except for "water" and "total," and the "total" is the total value of volatile and nonvolatile components. Fat emulsion A: 150 parts by mass Fat emulsion B: 50 parts by mass Cationic cellulose: 2 parts by mass Alkylamide derivative: 30 parts by mass Water: 9768 parts by mass Total: 10000 parts by mass

[0151] The ratio of the mass (g) of all nonvolatile components to the mass of the sizing agent for long glass fibers was 2.32 mass %. The composition ratio of the nonvolatile components is shown in Table 1.

[0152] (2) Glass yarn manufacturing Except for using the sizing agent for long glass fibers, a glass yarn was obtained under the same conditions as in Example 1. The obtained glass yarn had 50 filaments, a twist of 0.5Z, a count of 1.68 tex, and an ignition loss of 0.19% by mass.

[0153] (3) Glass cloth manufacturing A greige cloth and a glass cloth were produced under the same conditions as in Example 1, except that the obtained glass yarn was used and that a secondary sizing agent for the warp yarns had the same composition as the bundling agent for long glass fibers (Comparative Example 2).

[0154] The ignition loss of the obtained grey cloth was 1.2% by mass, the thickness was 18 μm, and the mass was 12.8 g / m 2 The ignition loss of the obtained glass cloth was 0.13% by mass, the thickness was 15 μm, and the mass was 12.5 g / m 2It was.

[0155] Comparative Example 3 (1) Manufacturing of sizing agents for long glass fibers The components were mixed to obtain the following composition to obtain a sizing agent for long glass fibers. Note that the parts by mass shown below are values ​​converted to the amount of nonvolatile components except for "water" and "total," and the "total" is the total value of volatile and nonvolatile components. Acrylic resin emulsion: 75 parts by weight Fat emulsion A: 150 parts by mass Fat emulsion B: 50 parts by mass Alkylamide derivative: 30 parts by mass Water: 9695 parts by mass Total: 10000 parts by mass

[0156] The ratio of the mass (g) of all non-volatile components to the mass of the sizing agent for long glass fibers was 3.05 mass %. The composition ratio of the non-volatile components is shown in Table 1.

[0157] (2) Glass yarn manufacturing Except for using the sizing agent for long glass fibers, a glass yarn was obtained under the same conditions as in Example 1. The obtained glass yarn had 50 filaments, a twist of 0.5Z, a count of 1.68 tex, and an ignition loss of 0.29% by mass.

[0158] (3) Glass cloth manufacturing A greige cloth and a glass cloth were produced under the same conditions as in Example 1, except that the obtained glass yarn was used and that a secondary sizing agent for the warp yarns had the same composition as the sizing agent for long glass fibers (Comparative Example 3).

[0159] The ignition loss of the obtained grey cloth was 1.1% by mass, the thickness was 18 μm, and the mass was 12.8 g / m 2 The ignition loss of the obtained glass cloth was 0.15% by mass, the thickness was 15 μm, and the mass was 12.5 g / m 2 It was.

[0160] Comparative Example 4 (1) Manufacturing of sizing agents for long glass fibers The components were mixed to obtain the following composition to obtain a sizing agent for long glass fibers. Note that the parts by mass shown below are values ​​converted to the amount of nonvolatile components except for "water" and "total," and the "total" is the total value of volatile and nonvolatile components. Acrylic resin emulsion: 75 parts by weight Fat emulsion A: 150 parts by mass Fat emulsion B: 50 parts by mass Polyoxyethylene alkyl ester: 15 parts by mass Alkylamide derivative: 30 parts by mass Water: 9680 parts by mass Total: 10000 parts by mass

[0161] The ratio of the mass (g) of all non-volatile components to the mass of the sizing agent for long glass fibers was 3.2 mass %. The composition ratio of the non-volatile components is shown in Table 1.

[0162] (2) Glass yarn manufacturing Except for using the sizing agent for long glass fibers, a glass yarn was obtained under the same conditions as in Example 1. The obtained glass yarn had 50 filaments, a twist of 0.5Z, a count of 1.68 tex, and an ignition loss of 0.31% by mass.

[0163] (3) Glass cloth manufacturing A greige cloth and a glass cloth were produced under the same conditions as in Example 1, except that the obtained glass yarn was used and that a secondary sizing agent for the warp yarns had the same composition as the sizing agent for long glass fibers (Comparative Example 4).

[0164] The ignition loss of the obtained grey cloth was 1.1% by mass, the thickness was 18 μm, and the mass was 12.8 g / m 2 The ignition loss of the obtained glass cloth was 0.21% by mass, the thickness was 15 μm, and the mass was 12.5 g / m 2 It was.

[0165] Comparative Example 5 (1) Preparation of glass yarn A glass yarn coated with starch (product name: BC3000 1 / 0 0.5Z X-4, manufactured by Unitika Glass Fiber Ltd.) was prepared. The long glass fibers constituting the glass yarn were made of E-glass, and the filament diameter was 4.1 μm. The glass yarn had 50 filaments, a twist of 0.5Z, a count of 1.68 tex, and an ignition loss of 1.00% by mass. The ignition loss of the glass yarn after heat treatment under heat treatment condition 1 was 0.16% by mass.

[0166] (2) Glass cloth manufacturing A greige cloth and a glass cloth were produced under the same conditions as in Example 1, except that the glass yarn was used and a secondary sizing agent for the warp yarns was used that contained polyvinyl alcohol as the main component.

[0167] The ignition loss of the obtained greige cloth was 2.4% by mass, the thickness was 18 μm, and the mass was 12.8 g / m 2 The ignition loss of the obtained glass cloth was 0.77% by mass, the thickness was 15 μm, and the mass was 12.5 g / m 2 It was.

[0168] 4. Evaluation Results The physical properties of the glass yarns and glass cloths obtained in Examples 1 to 6 and Comparative Examples 1 to 5 were measured, and the results are shown in Table 1.

[0169] [Table 1]

[0170] In Examples 1 to 6, the use of a sizing agent for long glass fibers containing an acrylic resin, oils and fats, and cationic cellulose or polyoxyethylene alkyl ether demonstrated an excellent effect of suppressing the generation of fluff, making the fibers suitable for the production of thin glass cloth for printed wiring boards. Furthermore, Examples 1 to 6 also demonstrated excellent heat cleaning properties at temperatures of 400°C or less, and the resulting glass yarns, even when produced by heat cleaning at temperatures of 400°C or less, were able to sufficiently suppress the occurrence of discoloration (burnt color) caused by insufficient heat cleaning.

[0171] In particular, in Examples 1 and 4 to 6, the fuzz suppression effect was significantly improved by using a sizing agent for long glass fibers in which the ratio of the total mass (g / L) of non-volatile components of the softener components to the mass (g / L) of all non-volatile components was 3 to 6% by mass.In particular, in Examples 4 to 6, the fuzz suppression effect was significantly improved by using a sizing agent for long glass fibers in which the ratio of the total mass (g / L) of non-volatile components of the softener components to the mass (g / L) of all non-volatile components was 3 to 6% by mass.

[0172] On the other hand, in Comparative Example 1, a sizing agent for long glass fibers that did not contain cationized cellulose or polyoxyethylene alkyl ether was used, and when heat cleaning treatment was performed at a temperature of 400°C or less, a color (burnt color) appeared on the glass cloth, and the heat cleaning property at a temperature of 400°C or less was poor.

[0173] In Comparative Example 2, a sizing agent for long glass fibers containing no acrylic resin was used, which was insufficient in its effect of suppressing fluffing and was not suitable for producing thin glass cloth for printed wiring boards. Furthermore, Comparative Example 2 also had poor heat cleaning properties at temperatures of 400°C or less.

[0174] In Comparative Example 3, a sizing agent for long glass fibers containing acrylic resin and oil but not containing cationized cellulose or polyoxyethylene alkyl ether was used, which was insufficient in its effect of suppressing fluffing and was not suitable for producing thin glass cloth for printed wiring boards. Furthermore, Comparative Example 3 also had poor heat cleaning properties at temperatures of 400°C or less.

[0175] Comparative Example 4 used a sizing agent for long glass fibers containing acrylic resin, oil and fat, and polyoxyethylene alkyl ester, and was inferior in heat cleaning properties at temperatures of 400°C or less.

[0176] Comparative Example 5 used starch alone as the film-forming component of the sizing agent for long glass fibers, and had poor heat cleaning properties at temperatures of 400°C or less.

Claims

1. A glass cloth formed from glass yarn made by bundling long glass fibers, The glass material constituting the long glass fibers is E-glass or a glass composition having a relative permittivity of less than 5.0 at a frequency of 1 MHz. The tensile strength of the glass yarn is 0.50 N / tex or more, and Glass cloth, wherein the aforementioned glass cloth has undergone heat cleaning treatment.

2. The glass cloth according to claim 1, used as a component material for printed circuit boards.