JP2011068549A - Glass fiber, method for manufacturing glass fiber, and glass fiber sheet-like object - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a homogeneous quality glass fiber in which there is no mixing of a hollow fiber relating to a glass fiber of fine count used for high density assembly of an electronic component, and heavily used as a structural material at a printed wiring board, and to provide a method for manufacturing the same, and a glass fiber sheet-like object. <P>SOLUTION: The glass fiber includes a composition comprising, by percentage by mass of oxide conversion, 70-80% of SiO<SB>2</SB>, 0-2% of Al<SB>2</SB>O<SB>3</SB>, 15-21.5% of B<SB>2</SB>O<SB>3</SB>, 0-1% of MgO, 0-2% of CaO, 0-2% of Li<SB>2</SB>O, 0-3% of Na<SB>2</SB>O, 0-3% of K<SB>2</SB>O, 0-3% of K<SB>2</SB>O, and 2-5% of Li<SB>2</SB>O+Na<SB>2</SB>O+K<SB>2</SB>O, wherein the content of SO<SB>3</SB>is at most 50 ppm. In the method for manufacturing the glass fiber, the melting is carried out so that a β-OH value obtained by an optical measurement may become at least 0.55/mm and at most 0.65/mm, and the glass fiber is manufactured by carrying out spinning. The glass fiber sheet-like object is used for an application in which the glass fiber is made composite with an organic resin material to form an organic resin composite material. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention is made of a glass composition having a low dielectric constant, a low dielectric loss tangent, and a low coefficient of thermal expansion, and has a dielectric loss when used in a printed wiring board that requires high-density mounting used in electronic parts and the like. The present invention relates to a glass fiber from which a small and highly reliable printed wiring board can be obtained, a method for producing the glass fiber, and a glass fiber sheet-like material constituted thereby.

  With the development of various electronic devices that support the information industry, technologies related to mobile phones, personal digital assistants (PDAs), etc. are making remarkable progress. In these electronic devices, a large number of electronic components such as resistors, capacitors, and integrated circuits are mounted on a printed wiring board (printed circuit board, rigid board, printed board, or printed wiring board) by an unprecedented high-density mounting technology. It is mounted at a high density. The printed wiring board is a sheet-shaped composite material in which glass fibers, a resin material, a modifier, and the like are mixed in appropriate amounts. Many electronic components mounted on the printed wiring board are arranged on the substrate by through holes or the like provided in the printed wiring board. This printed wiring board may be represented by another name such as a module, a board, a unit, or a package depending on its function and application.

E glass is well known as a glass fiber for this printed wiring board application. This E glass is a material excellent in electrical insulation, excellent in spinnability when manufactured as a glass fiber from a molten state, and excellent in workability such as cutting. Therefore, E glass, there are many uses proven, its specific glass composition, for example, as represented by mass percentage terms of _{oxides, SiO 2 52~56%, Al 2} O 3 12~16%, B ₂ O ₃ 5-10%, CaO 16-25%, MgO 0-5%, alkali metal oxide (R ₂ O) 0-2%, Fe ₂ O ₃ 0.05-0.4%, F ₂ 0 -1.0%.

On the other hand, for printed wiring boards, in recent years, in order to realize high-speed signal processing, signal transmission speed has been increased by using high frequency. In this case, the electrical characteristics of the printed wiring board are regarded as important. In order to improve the transmission speed inversely proportional to the square root of the dielectric constant of the material, it is necessary that the material constituting the printed wiring board has a low dielectric constant. In addition, the dielectric loss related to the heat generation of the printed wiring board is required to be small. For this purpose, a material having a small dielectric loss tangent is required. Incidentally, the dielectric constant in the present invention means a relative dielectric constant which is a ratio of a dielectric constant of a medium and a dielectric constant of a vacuum. In general, when an alternating current is passed through the glass, the glass absorbs energy with respect to the alternating current and generates heat. The absorbed dielectric loss energy is proportional to the dielectric constant and dielectric loss tangent determined by the glass component and structure, and is expressed as W = kfv ² × εtan δ. Here, W is a dielectric loss energy, k is a constant, f is a frequency, v ² is a potential gradient, ε is a dielectric constant, and tan δ is a dielectric loss tangent. From this equation, it can be seen that the larger the dielectric constant ε and the dielectric loss tangent tan δ of the glass composition and the higher the frequency f, the larger the dielectric loss. Therefore, in order to reduce the dielectric loss, it is required to reduce the dielectric constant ε and the dielectric loss tangent tan δ of the glass composition.

For this reason, a glass fiber material for a printed wiring board having a low dielectric constant ε and a low dielectric loss tangent tan δ is required for the glass fiber used for the printed wiring board. Patent Document 1 discloses E glass (at room temperature). A glass material called D glass is disclosed in order to realize a dielectric constant and a dielectric loss tangent lower than a dielectric constant ε at a frequency of 1 MHz and a dielectric loss tangent tan δ of 12 × 10 ⁻⁴ . This D glass is, for example, expressed in terms of mass percentage in terms of oxide, SiO ₂ 74.6%, Al ₂ O ₃ 1.0%, B ₂ O ₃ 20.0%, MgO 0.5%, CaO 0. The glass material is 4%, Li ₂ O 0.5%, Na ₂ O 2.0%, K ₂ O 1.0%, and the dielectric constant of 1 MHz of this glass is about 4.4.

Patent Document 2 includes, in mass%, SiO ₂ 50-60%, Al ₂ O ₃ 10-18%, B ₂ O ₃ 18-25%, CaO 0-10%, MgO 1-10%, Li ₂ O + Na. A low dielectric constant glass fiber having a glass composition of ₂ O + K ₂ O 0 to 1.0% and Fe ₂ O ₃ 0.1 to 1% is disclosed.

Patent Document 3, in _{mass%, SiO 2 50~60%, Al} 2 O 3 10~20%, B 2 O 3 20~30%, CaO 0~5%, 0~4% MgO, Li 2 O + Na A low dielectric constant glass fiber having a composition of ₂ O + K ₂ O 0-0.5% and TiO ₂ 0.5-5% is disclosed.

Further, Patent Document 4, in _{mass%, SiO 2 48~80%, Al} 2 O 3 0~18%, B 2 O 3 11~35%, 0~10% MgO, CaO 0~10%, Li 2 It has a composition of O + Na ₂ O + K ₂ O 0-7% and TiO ₂ less than 3%, H ₂ O <800 ppm, dielectric constant is 5.0 or less at 1 MHz, and dielectric loss tangent is 7 × 10 ⁻⁴ or less. A low dielectric constant, low dielectric loss tangent glass characterized in that is disclosed.

JP-A-63-2831 Japanese Patent Laid-Open No. 10-167759 JP-A-8-333137 JP 2003-137590 A

  However, the inventions so far are not sufficient in terms of efficiently producing high-quality glass fibers suitable for use in printed wiring boards and the like for high-density mounting. Glass fibers used for printed wiring boards are generally produced by drawing glass fibers from molten glass kept at a high temperature. During the production, hollow fibers called hollow fibers due to bubbles mixed in the glass may occur very rarely. This hollow fiber is generated by drawing bubbles in the molten glass along the drawing direction in the glass fiber when the glass fiber is spun. Such a hollow fiber not only greatly affects the physical performance such as the strength of the glass fiber, but may become a fatal defect such as an insulation failure of the printed wiring board. Hollow fibers are also regarded as one of the causes of reduced insulation reliability. That is, in the printed wiring board of higher density mounting, the number of holes is increased and the distance between the printed wiring boards is reduced, and there is a concern that the reliability is lowered due to the hollow fiber. Therefore, when manufacturing a printed wiring board, it is requested | required that a hollow fiber, ie, a hollow fiber, should not be mixed in glass fiber.

  Further, with the development of high-density packaging, glass fibers (thin count filaments) with a monofilament diameter thinner than before have been required for printed wiring boards. This is because, as the finer count fiber is used, the drilling position of the printed wiring board can be finely finished. However, it is pointed out that the fine glass fiber has to be strictly controlled in the viscosity of the molten glass, requires a high level of homogeneity during melting, and is difficult to adjust the fiber diameter.

  In view of the above-described situation, the present invention relates to a fine count glass fiber frequently used as a structural material in applications such as a printed wiring board used for high-density mounting of electronic components, and has a low dielectric constant, a low dielectric loss tangent, and a low heat ray. It is made of a glass composition having an expansion coefficient, does not contain hollow fibers, and provides a glass fiber of uniform quality suitable for a constituent material such as a printed wiring board, and a method for producing the same, and a glass fiber obtained using the glass fiber It relates to a sheet-like material.

  The present inventors pay attention to a trace amount component in the glass composition for glass fiber, find that a glass fiber not mixed with hollow fibers can be obtained by limiting the content to a predetermined range, and present the contents thereof. Is.

Glass fibers of the present invention, as represented by mass percentage terms of _{oxides, SiO 2 70~80%, Al 2} O 3 0~2%, B 2 O 3 15~21.5%, 0~1% MgO, CaO _{0~2%, Li 2 O 0~2%} , containing _{Na 2 O 0~3%, K 2} O 0~3%, Li 2 O + Na 2 O + K 2 O 2~5% of the composition, containing the SO ₃ The amount is 50 ppm or less.

  The glass fiber of this invention can specify the chemical composition by using various analysis means, such as a chemical analysis and an instrumental analysis.

In the present invention, when displaying each element component constituting the glass fibers in terms of oxide, the glass composition, SiO ₂ component is in the range from 70 wt% to 80 wt%, Al ₂ O ₃ component is 0 mass% To 2 mass%, B ₂ O ₃ component is in the range of 15 mass% to 21.5 mass%, MgO component is in the range of 0 mass% to 1 mass%, and CaO component is 0 mass%. To 2% by mass, Li ₂ O component in the range of 0 to 2% by mass, Na ₂ O component in the range of 0 to 3% by mass, and K ₂ O component in the range of 0 to 3% by mass. The total amount of the Li ₂ O component, the Na ₂ O component, and the K ₂ O component is in the range of 2% by mass to 5% by mass, and the SO ₃ component is 50 ppm or less.

  The reason for limiting the content of each component described above will be described below.

The SiO ₂ component is a component that forms a skeleton of the network structure in the glass structure, and is a main component of the glass composition of the present invention, and the glass content increases as the content of the SiO ₂ component in the glass composition increases. The structural strength tends to increase. As the structural strength of the glass increases, the chemical durability also increases, and in particular, the acid resistance has high performance. In order to maintain the strength of the glass structure in a sufficient state and have a stable quality, the content of the SiO ₂ component needs to be at least 70% by mass or more. On the other hand, when the content of the SiO ₂ component in the glass composition increases, the high temperature viscosity value of the molten glass increases, and as a result, such a glass composition will be produced with high efficiency and homogeneity by the melting method. If so, expensive equipment is required. Moreover, the molding temperature at the time of shaping | molding as glass fiber becomes high. Therefore, there may be restrictions in terms of equipment management during manufacturing. Also, when melting glass, it is easy to obtain a homogeneous molten glass in which bubbles generated during the vitrification reaction do not remain, so that excessive thermal energy is not required for melting the glass, and when producing glass fibers In order to ensure high spinnability, the content of the SiO ₂ component needs to be 80% by mass or less. In view of the above, the SiO ₂ component is expressed in terms of oxide percentage, and is preferably 72% by mass or more and 78% by mass or less, that is, SiO ₂ is preferably 72 to 78% by mass, and more preferably SiO ₂ 73 to 73% by mass. 77 wt%, more preferably be a _SiO 2 74 to 77 wt%.

The Al ₂ O ₃ component is a component that suppresses the phase separation of the glass and improves the water resistance, but when it is contained in an amount of 2% by mass or more, the dielectric constant ε increases and the phase separation property deteriorates. Deterioration of the phase separation property of the glass is not preferable because it leads to deterioration of acid resistance of the obtained glass fiber. Here, the phase separation means a phenomenon in which the glass is separated into two or more glass phases. From such a viewpoint, the Al ₂ O ₃ component is expressed as a percentage in terms of oxide, more preferably 1.8% by mass or less, that is, Al ₂ O ₃ 0 to 1.8% by mass, Preferably it is 0-1.4 mass%, More preferably, it is 0-1.2 mass%.

B ₂ O ₃ component in the glass network structure like the SiO ₂ component is a component forming the skeleton, rather than to increase the high temperature viscosity of the glass melt as SiO ₂ component, but rather lower the high temperature viscosity There is a work to make. Therefore, the B ₂ O ₃ component has both roles of keeping the dielectric constant ε of the molded glass low and suppressing the increase in the high temperature viscosity of the molten glass. When the content of the B ₂ O ₃ component in the glass composition is less than 15% by mass, the glass is maintained at a dielectric constant ε of 4.5 or less, and the molten glass at a spinning temperature of 10 ^3.0 dPa · s. It may be difficult to make the temperature below 1400 ° C. at which sufficient spinnability can be ensured. On the other hand, when the content of the B ₂ O ₃ component in the glass composition is too large, the volatilization amount of the B ₂ O ₃ component increases during melting, and it may be difficult to maintain the molten glass in a homogeneous state. is there. On the other hand, if the content of the B ₂ O ₃ component is too large, the water resistance is lowered and the strain point is lowered. From such a viewpoint, if the B ₂ O ₃ component in the glass composition exceeds 21.5% by mass, the acid resistance and phase separation properties of the glass deteriorate, which is not preferable. From the above viewpoint, the B ₂ O ₃ component is expressed as a percentage in terms of oxide, and more preferably 16% by mass or more and 21.0% by mass or less, that is, B ₂ O ₃ 16 to 21.0% by mass. More preferably, it is 17-20.7 mass%, More preferably, it is 18-20.5 mass%.

The MgO component is a component having a function as a flux that makes it easy to melt the glass raw material, and at the same time, is very effective in reducing the high temperature viscosity corresponding to a temperature of 10 ^2.0 dPa · s. Helps to make bubbles out of foam and make homogeneous glass. However, if the content of the MgO component in the glass composition exceeds 1%, the dielectric constant ε and the dielectric loss tangent tan δ are increased. From the above viewpoint, the MgO component is expressed as a percentage in terms of oxide and is 1% by mass or less, more preferably 0.9% by mass or less, that is, 0 to 0.9% by mass, and more preferably 0 to 0% by mass. It is 0.8 mass%, More preferably, it is 0 to 0.7 mass%.

The CaO component is a component having a function as a flux that makes it easy to melt a glass raw material, and at the same time, is very effective in lowering the high temperature viscosity corresponding to a temperature of 10 ^2.0 dPa · s. Helps to make bubbles out of foam and make homogeneous glass. However, if the content of the CaO component in the glass composition exceeds 2%, the dielectric constant ε and the dielectric loss tangent tan δ are increased. From the above viewpoint, the CaO component is expressed as a percentage in terms of oxide, and is 2.0% by mass or less, more preferably 1.5% by mass or less, that is, 0 to 1.5% by mass, more preferably 0 to 1.0% by mass, and more preferably 0 to 0.8% by mass.

Li 2 _O component, the alkali metal oxide component oxides conversion display in the glass composition, expressed as Na 2 _O component or K _{2 O} component, the glass melt is heated in a state of mixing a plurality of glass raw material In this case, it functions as a so-called flux that facilitates the production of a glass melt, and also has a function of lowering the high-temperature viscosity. However, Li ₂ O component, Na ₂ O component or _{K 2} O component, the both increased content in the glass composition, the dielectric constant of the glass ε increases, because the water resistance is poor, Li ₂ O component Is up to 2% by mass, and the upper limit of each of the Na ₂ O component and the K ₂ O component is 3% by mass. In addition, when the total amount of Li ₂ O, Na ₂ O, and K ₂ O is 2% by mass or less, the high-temperature viscosity of the molten glass is increased and the meltability is deteriorated. The dielectric constant ε is 4.5 or more and the dielectric loss tangent tan δ is 0.003 or more. From the above viewpoint, the upper limit of the Li ₂ O component is expressed as a percentage in terms of oxide, more preferably up to 1.5% by mass, that is, 0 to 1.5% by mass, and more preferably 0 to 1%. .3% by mass. The upper limit of each of the Na ₂ O component and the K ₂ O component is expressed as a percentage in terms of oxide, more preferably up to 2.8% by mass, that is, 0 to 2.8% by mass, and more preferably Is from 0 to 2.5 mass%, more preferably from 0 to 2.2 mass%. The total amount of the Li ₂ O component, Na ₂ O component, and K ₂ O component is more preferably 2.3% by mass to 4.5% by mass, that is, 2.3 to 4.5% by mass. More preferably, it is 2.7 to 4.2% by mass, and more preferably 3.0 to 3.9% by mass.

The SO ₃ component is a component that acts as a fining agent in the molten glass. However, when the residual amount in the glass fiber is 50 ppm or more, bubbles remain in the molten glass, or bubbles are generated by reboil near the bushing. This is not preferable because it causes the generation of hollow fibers. In order to reduce the hollow fiber, the smaller the SO ₃ component in the glass fiber, the better, more preferably 30 ppm or less, and even more preferably 15 ppm or less. For example, even when SO ₃ is intentionally or contained as an impurity in a glass raw material batch, the glass melting temperature is sufficiently raised before spinning as glass fiber, and the amount of dissolved SO ₃ component in the glass is reduced. Therefore, it is necessary to release it from the molten glass as SO ₂ gas to 50 ppm or less. The SO ₃ component analysis method may be carried out using an ion chromatograph, for example, by decomposing a sample using alkali melting.

  Moreover, if the glass fiber of this invention does not contain As, Sb, F, and Cl substantially in addition to the above, since it does not contain an environmental load substance and becomes a product in consideration of the environment, it is preferable. “Substantially free” means that components mixed as impurities are excluded from refractories and raw materials at the time of melting. Specifically, each component is expressed in terms of oxide. And 1000 ppm or less.

  As, Sb, F, and Cl are also components that act as fining agents, but it is preferable that they are not substantially included in view of environmental burden.

In the present invention, as a fining agent added to the above, may contain CeO ₂ component 2 mass%. The clarification effect of the CeO ₂ component appears more clearly in terms of oxide mass percentage expressed as 0.01% by mass or more, more preferably 0.05% by mass or more, and most preferably 0.10% by mass. % Or more. However, if the CeO ₂ component is added in a large amount, it may affect the devitrification property of the molten glass. From such a viewpoint, the CeO ₂ component should not exceed 2% in terms of oxide-based mass percentage. By containing the CeO ₂ component, it becomes easier to achieve non-hollowing of the glass fiber.

  In addition to the above, the glass fiber of the present invention has a viscosity at the refining stage of the molten glass if the β-OH value obtained by optical measurement is 0.55 / mm or more and 0.65 / mm or less. It is possible to promote clarification by reducing the content of β-OH, which is difficult to dissolve (there is a risk of yarn breakage in spinning at an insufficiently homogenized portion such as a knot). Melting is promoted, which leads to suppression of foam formation and expansion in the molten glass, which is preferable because it prevents the formation of hollow fibers during spinning.

The β-OH value obtained by optical measurement is 0.55 / mm or more and 0.65 / mm or less because the minimum infrared ray generated in the vicinity of 3600 cm ^{−1 due to} vibration of the β-OH bond structure of glass. For the ratio obtained using the transmittance as the denominator and the infrared transmittance at the reference wavelength (3846 cm ⁻¹ ) as the numerator, the value of the common logarithm (the logarithm with 10 as the base) is divided by the thickness of the glass sample to be inspected. This means that the measured value is within the range of 0.55 / mm to 0.65 / mm. In other words, the equation for calculating the β-OH value is the following equation (1).

In Equation ¹ , T is the light transmission thickness (mm) of the glass sample, A is the transmittance (%) at the reference wavelength (3846 cm ⁻¹ ), and B is the minimum transmittance of infrared rays generated near 3600 cm ^−1. Value (%).

  When the β-OH value obtained by optical measurement is less than 0.55 / mm, the effect of reducing the viscosity or the effect of reducing the hardly soluble component may not be sufficiently obtained. The glass fiber of the present invention is often produced using a heat-resistant container called a bushing mainly composed of a noble metal component mainly composed of platinum. The bushing includes a large number of heat-resistant nozzles, and a large number of glass fibers are drawn out from the heat-resistant nozzles as a thin molten glass stream and cooled to form glass fibers. When the β-OH value is less than 0.55 / mm, sufficient melting cannot be performed to degas the bubbles originating from the raw material, and the bubbles remain. In addition, bubbles in a state in which they are taken into the hardly soluble component are likely to flow out as they are, and the nozzles are clogged during spinning or yarn breakage is likely to occur. As a result of the bubble generation and expansion behavior in the molten glass, hollow fibers are likely to be formed during spinning. From the above viewpoint, the β-OH value is more preferably 0.55 / mm or more, further preferably 0.555 / mm or more, more preferably 0.560 / mm or more, and still more preferably 0.565. / Mm or more, and most preferably 0.568 / mm or more.

  Further, when the β-OH value exceeds 0.65 / mm, the viscosity of the molten glass shifts to become smaller, but the viscosity tends to fluctuate significantly, and the diameter of the glass fiber to be spun is controlled. Adjustment becomes difficult. From the above viewpoint, the β-OH value is 0.645 / mm or less, more preferably the β-OH value is 0.643 / mm or less.

Moreover, the glass fiber of this invention can add various components as needed in the range which does not have big influence on the performance of the glass fiber of this invention in addition to the above-mentioned. Configuration if specifically exemplified what can be used as a component, the content of 3% by _{ZrO 2, P 2 O 5,} Fe 2 O 3 or the like by mass percentage of glass composition for glass fiber of the present invention If present, it can be contained.

In addition to the above, trace components can be contained up to 0.1% in terms of mass%. For example, various trace components such as Cr ₂ O ₃ and MoO ₃ are applicable.

  Moreover, in the glass fiber of this invention, if there is no big influence on the performance of glass fiber, a trace amount of noble metal elements may contain in glass. For example, a white metal element such as Pt, Rh, and Os may be contained up to 1000 ppm, that is, the content of the metal element expressed as a mass percentage up to 0.1%.

If the dielectric constant ε at a frequency of 1 MHz is 4.5 or less and the dielectric loss tangent is 20 × 10 ⁻⁴ or less in addition to the above, the glass fiber of the present invention has a dielectric loss of a printed wiring board using glass fiber. Is preferable.

In addition to the above, the glass fiber of the present invention is a printed wiring board that uses a high frequency if the dielectric constant ε at a frequency of 10 GHz is 4.5 or less and the dielectric loss tangent is 60 × 10 ⁻⁴ or less. This is preferable because the loss is further reduced.

  In addition to the above, the glass fiber of the present invention has a sufficiently high electrical resistance if the volume electrical resistivity log ρ at 150 ° C. is 12.8 Ω · cm or more. Will be demonstrated.

In addition to the above, the glass fiber of the present invention can be efficiently produced without significant changes to the glass fiber spinning device and spinning method, provided that the temperature Ty of 10 ^3.0 dPa · s is less than 1400 ° C. This is preferable.

  If the glass fiber of the present invention is a so-called fine count having an average value of the diameter of the glass fiber of 3 μm or more and 9.5 μm or less, particularly 3 μm or more and 5 μm or less, a printed wiring board that requires high density and thinning is particularly required. When applied to the above-mentioned uses, the performance of the composite material for printed wiring board applications constituted by using such glass fibers having a small fiber diameter is greatly improved.

  When the average diameter of the glass fibers, that is, the glass filaments is less than 3 μm, the fiber diameter becomes too small, so that the production yield of the glass fibers may be lowered.

  On the other hand, when the average value of the diameter of the glass filament exceeds 9.5 μm, the fiber diameter is too large and it is not suitable as a glass fiber for a printed wiring board.

  From the above viewpoints, the glass fiber of the present invention preferably has an average diameter of the glass filament in the range of 3.1 μm or more and 9.2 μm or less, and more preferably 3.2 μm or more and 7.2 μm. It is within the following range, more preferably within the range of 3.3 μm to 5.5 μm, even more preferably within the range of 3.4 μm to 5.2 μm, most preferably It is to be 3.8 μm or more and 4.8 μm or less.

  In addition to the above, the glass fiber of the present invention can provide a highly reliable printed wiring board if the number of hollow fibers per 100 mm of glass filament length is 3 / 100,000 filaments or less.

  The number of hollow fibers per glass filament length of 100 mm is 3 / 100,000 filaments or less means that the number of hollow fibers per 100,000 filaments is 3 or less for a filament with a glass filament length of 100 mm. ing. The number of hollow fibers is measured by immersing the glass cloth in an immersion liquid adjusted to have the same refractive index as that of the glass fiber, and observing it under a microscope (50 times) of the transmitted light. It can be easily obtained by measuring the number of fibers and dividing the value by the number of observed filaments and multiplying by 100,000.

  From the above viewpoint, the glass fiber of the present invention is more preferably 2 pieces / 100,000 filaments or less, more preferably 1 piece / 100,000 filaments or less per 100 mm of the glass filament length, most preferably 0.00. 5 pieces / 100,000 filaments or less.

  About glass fiber, it is good also as what apply | coated to the surface the coating agent which provides a desired physicochemical performance. Specifically, a sizing agent, an antistatic agent, a surfactant, an antioxidant, a film forming agent, a coupling agent or a lubricant may be coated.

  Examples of silane coupling agents that can be used for glass fiber surface treatment include γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacrylic acid. Roxypropyltrimethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, N-β- (N-vinylbenzylaminoethyl) -γ- There are aminopropyltrimethoxysilane / hydrochloride, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, vinyltriethoxysilane, etc., and select appropriately according to the type of resin to be combined with the glass fiber used Also good.

  The glass fiber of the present invention has a CV (Coefficient of Variation) value of 12% obtained by dividing the standard deviation of the fiber diameter by the average value of the fiber diameter in addition to the above, and multiplying that value by 100. A glass having a small fiber diameter, in addition to a printed wiring board, in addition to a printed wiring board, as long as a plurality of glass filaments in the form of chopped strands, yarns, or rovings are used. It can be used in various cases where fibers are required. Incidentally, the CV value is also called a coefficient of variation, and is a value obtained by calculating the degree of dispersion excluding the influence of the scale from the standard deviation. If the CV value of the glass fiber exceeds 12%, it is not preferable because the glass fiber that requires a precise shape has a problem in its formability. When the CV value is expressed by a mathematical formula, the formula shown in Equation 2 is obtained.

  A plurality of glass filaments having a glass fiber diameter CV value of 12% or less in the form of chopped strands, yarns or rovings means that the glass fiber production apparatus has a CV value of 12% or less. Spinning by adjusting the conditions, the obtained glass fiber is made into a chopped glass chopped strand, or a twisted yarn, or a roving obtained by winding a plurality of glass filaments in a wound state It represents that. Incidentally, the standard deviation and the average value of the fiber diameter are calculated from the measured values for 200 glass filaments.

  In order to control the CV value of the glass fiber diameter to be 12% or less, for example, when using a glass forming apparatus in which a large number of heat-resistant nozzles are arranged in the bushing, the nozzle hole diameter, nozzle length, nozzle Each condition of the temperature, the ambient air temperature around the nozzle, the nozzle head pressure, the air blowing speed, and the glass filament drawing speed may be determined so as to be optimal for the glass fiber composition of the present invention.

  If the glass fiber of the present invention is a glass fiber having a CV value of 12% or less in the form of chopped strand, yarn or roving, a plurality of glass filaments having a CV value of 12% or less can be used. A drilling position generated by misalignment of the drill tip in the drilling process to form a through hole by using a glass cloth that is opened and widened when used in printed wiring board applications. It is preferable because the accuracy of the drilling position can be improved by suppressing the fluctuations.

  Moreover, the glass fiber of this invention may be manufactured by what kind of manufacturing method, as long as desired performance is realizable. For example, various production methods such as a direct molding method (DM method: direct melt method) and an indirect molding method (MM method: marble melt method) may be employed depending on the application and production amount. That is, the glass fiber of the present invention may be any glass fiber that has been spun by obtaining a glass fiber having a predetermined diameter by drawing the glass fiber from a bushing having a heat-resistant nozzle in addition to the above.

  Moreover, if the glass fiber of this invention is used for a printed wiring board in addition to the above, the glass fiber of a fine count can comprise a high quality printed wiring board.

  The glass fiber of the present invention constitutes a high-density printed wiring board as long as it is used for the purpose of forming an organic resin composite material by being combined with an organic resin material as a glass cloth or a nonwoven fabric in addition to the above. Since it becomes an optimal glass fiber above, it is preferable.

  In other words, the glass cloth or the one used as a nonwoven fabric to be combined with an organic resin material to form an organic resin composite material is a glass cloth used as a warp and a weft for various glass cloths for printed wiring boards. The woven fabric is woven by the weaving method, or the chopped strand is used as a glass paper by a wet method or a dry method, and is used for forming an organic resin composite by compounding these with an organic resin material. .

  In the case of the glass cloth obtained by using the glass fiber of the present invention, the glass fiber constituting the glass cloth is, for example, 1 tex or more and 75 tex or less, preferably 1.5 tex or more and 25 tex or less, more preferably 1.5 tex or more and 15 tex or less. It is the following, and no special limitation is required for the cross-sectional shape of the glass filament constituting the bundled glass strand. The cross-sectional shape of the glass filament may be circular, elliptical, or oval. The twist number of the glass fiber bundle is more preferably 2 times / 25 mm or less.

  The glass cloth obtained by using the glass fiber of the present invention has 30 to 100 warps per warm and 25 mm of wefts, preferably 45 to 90 warps and 35 wefts. A glass cloth having a configuration of 90 or more is more preferable.

  When the woven product obtained using the glass fiber of the present invention is used as a constituent material of a printed wiring board, the production process is specifically as follows. That is, the glass yarn unwound from the package of the glass yarn wound body made of the composition for glass fiber of the present invention is warped with a warper, and is secondarily sized with a gluing machine and wound from a beam to a room beam. Use warp. The package of the glass yarn wound body is unwound, this is used for the weft, and the glass cloth is woven using an air jet loom or the like. Organic components adhering to the woven glass cloth are removed by incineration by heating (heat deoiling), immersed in a treatment solution containing a silane coupling agent and dried (surface treatment), and then impregnated with resin. A laminated board for a printed wiring board is manufactured by laminating and curing the resin.

  Moreover, when the glass paper obtained using the glass fiber of this invention uses a chopped strand, the length dimension of the chopped strand is not limited. In other words, the fiber length dimension can be selected according to the application. Further, any method for producing chopped strands can be adopted. The strand spun from the melt process can be cut immediately after spinning, or once wound as a continuous fiber, it may be cut by a cutting device according to the application. In this case, any method can be adopted as a cutting method. For example, an outer peripheral blade cutting device, an inner peripheral blade cutting device, or the like can be used. Moreover, it does not specifically limit about the aggregate form of a chopped strand.

  Moreover, you may use together the fiber material other than the glass fiber of this invention, a solid additive, and a liquid additive for the glass cloth and glass paper obtained using the glass fiber of this invention according to a use. In addition, as a fiber material other than the glass fiber of the present invention to be used in combination with the glass fiber material of the present invention when constituting glass cloth or glass paper, E glass fiber, glass fiber of other composition, organic fiber material, ceramic fiber And carbon fibers may be used. Solid additives include ceramic powder, organic resin powder, and silicone powder. Liquid additives include polymerization accelerators, polymerization inhibitors, antioxidants, and decomposition. Appropriate amounts of reaction inhibitors, diluents, antistatic agents, anti-aggregation agents, modifiers, wetting agents, drying agents, antifungal agents, dispersants, curing accelerators, reaction accelerators, thickeners or reaction accelerators May be used.

  The glass fiber production method of the present invention is obtained by melting and spinning so that the β-OH value obtained by optical measurement is 0.59 / mm or more and 0.65 / mm or less. It is characterized by producing fibers.

Here, the glass fiber of the present invention is produced by melting and spinning so that the β-OH value obtained by optical measurement is 0.55 / mm or more and 0.65 / mm or less. It ’s like that. That is, it is a glass fiber obtained by heating various glass raw materials (including cullet etc.) to a high temperature to melt them, and spinning them from a nozzle attached to a bushing after homogenization. in mass percentage _{conversion, SiO 2 70~80%, Al 2} O 3 0~2%, B 2 O 3 15~21.5%, 0~1% MgO, CaO 0~2%, Li 2 O 0 ˜2%, Na ₂ O 0 to 3%, K ₂ O 0 to 3%, Li ₂ O + Na ₂ O + K ₂ O 2 to 5% in composition, SO ₃ content should be 50 ppm or less In other words, the moisture content of the glass is limited so that the β-OH value of the glass obtained by optical measurement is 0.55 / mm or more and 0.65 / mm or less.

  In order for the β-OH value of the glass to be 0.55 / mm or more and 0.65 / mm or less, selection of glass raw material components, cullet rate, temperature and time of molten glass, oxygen partial pressure, molten glass The atmosphere of the upper surface of the liquid surface, the bushing and the nozzle, and the dissolved gas component in the ambient atmosphere of the melting tank may be appropriately managed. In addition, when the melting is divided into multiple times and the other stages of melting are performed as primary melting, secondary melting, etc., if the melting stage governing the value of β-OH value is known, only that stage will be focused You may manage. It is sufficient that these mutual conditions be between the upper limit value and the lower limit value of the β-OH value in the molten glass, and that spinning can be realized stably. The β-OH value may be 0.55 / mm or more and 0.65 / mm or less.

  In addition, the glass fiber sheet-like material of the present invention is formed by forming the glass fiber of the present invention into a sheet shape, and is used for an application in which an organic resin composite material is formed by being combined with an organic resin material. .

Here, the glass fiber of the present invention will be formed into a sheet, and are used in applications for forming the organic resin composite material is complexed with an organic resin material, SiO ₂ 70 with mass percentage of the oxide equivalent _{~80%, Al 2 O 3 0~2} %, B 2 O 3 15~21.5%, 0~1% MgO, CaO 0~2%, Li 2 O 0~2%, Na 2 O 0~3 %, K ₂ O 0 to 3%, Li ₂ O + Na ₂ O + K ₂ O 2 to 5% glass fiber sheet having a SO ₃ content of 50 ppm or less and a glass fiber sheet having a thickness of 1 mm or less It is meant to be used in applications where an organic resin composite material is obtained by impregnating a thermosetting organic resin material.

  For example, a resin such as a phenol resin, an epoxy resin, a polyimide resin, or a bismaleimide resin may be used as the organic resin material having thermosetting properties.

  Moreover, if the glass fiber sheet of this invention is a glass cloth or glass paper in addition to the above, the printed wiring board which exhibits various performance according to a use can be manufactured.

  As the glass cloth, woven fabrics having various structures can be employed. For example, it is possible to use a woven structure such as a plain weave or a twill weave to a more complicated structure. Further, the glass paper may be any glass paper as long as it is chopped strands, dispersed as a monofilament in white water, and then formed into a sheet using an organic binder. For example, in the case of using chopped strands, the molten glass obtained by melting the glass fiber of the present invention described above is continuously drawn out from a heat-resistant nozzle disposed in a molding apparatus such as a bushing, and a sizing agent or the like is provided around the glass. Cover and mold. Next, the obtained long glass fiber is wound around a paper tube or the like to make a cake (also called cheese), and then the necessary number is pulled out from the cake and cut to a predetermined length by a glass fiber cutting device. To do. After the chopped strands thus obtained are dispersed in white water, they are picked up on a mesh, randomly deposited on a conveyor to form a sheet, and a liquid binder is sprayed from above to bond this By curing the agent, a glass fiber sheet-like material constituted by the glass chopped strands is obtained through a step of bonding the glass chopped strands to each other.

1 glass fibers of the present invention, as represented by mass percentage terms of _{oxides, SiO 2 70~80%, Al 2} O 3 0~2%, B 2 O 3 15~21.5%, MgO 0~1 %, CaO 0-2%, Li ₂ O 0-2%, Na ₂ O 0-3%, K ₂ O 0-3%, Li ₂ O + Na ₂ O + K ₂ O 2-5%, _Since the content of ₃ is 50 ppm or less, no bubbles remain in the molten glass or bubbles are not generated by reboil in the vicinity of the bushing, and the number of hollow fibers in the glass fiber is small and obtained. The glass fiber has excellent electrical performance such as dielectric constant ε and dielectric loss tangent tan δ.

  (2) If the glass fiber of this invention does not contain As, Sb, F, and Cl substantially, since an environmental load will become small, it is preferable.

  (3) If the β-OH value obtained by optical measurement of the glass fiber of the present invention is 0.55 / mm or more and 0.65 / mm or less, clarification at the time of melting is promoted and the viscosity is increased. A large heterogeneous component adversely affects spinning, and does not lead to an increase in the chance of producing hollow fibers, which is preferable because it makes it easier to obtain glass fibers of stable quality.

  (4) If the glass fiber of the present invention has 3 hollow fibers per 100 mm of glass filament length / 100,000 filaments or less, a high-quality composite material can be obtained. It will be something to be demonstrated.

  (5) If the glass fiber of this invention is used for a printed wiring board, it is especially suitable when implement | achieving high-density mounting.

  (6) If the glass fiber of this invention is used for the use which combines with an organic resin material as a glass cloth or a nonwoven fabric and is used for the use which forms an organic resin composite material, according to a use, the glass fiber which has high performance is used. Therefore, it is possible to improve the dielectric properties and heat resistance of a printed wiring board applied to various electronic circuits.

  (7) The glass fiber manufacturing method of the present invention is claimed by melting and spinning so that the β-OH value obtained by optical measurement is 0.55 / mm or more and 0.65 / mm or less. Since the glass fiber according to any one of Items 1 to 6 is manufactured, it is easy to suppress the mixing of hollow fibers and to continue to efficiently produce stable fine count glass fibers.

  (8) The glass fiber sheet-like material of the present invention is a conventional process as long as it is used for the purpose of forming an organic resin composite material by forming a glass fiber into a sheet shape and composited with an organic resin material. It is suitable for manufacturing a printed wiring board that exhibits high quality and stable performance manufactured without changing the above.

  (9) Since the glass fiber sheet-like material of the present invention is a glass cloth or glass paper, it is manufactured without changing manufacturing conditions when manufacturing a prepreg used in a process of manufacturing a printed wiring board. Therefore, the present invention is suitable for obtaining a printed wiring board that can be used even in an environment where the temperature changes rapidly without hindering the manufacturing process of the printed wiring board.

  Below, the glass fiber of this invention, its manufacturing method, and the glass fiber sheet-like thing using the glass fiber of this invention are demonstrated concretely.

  Table 1 summarizes the chemical composition of the glass fibers used in the series of evaluations and the properties of the glass fibers obtained by melting in relation to the examples of the present invention. First, in order to obtain the glass fiber composition of the present invention, a predetermined amount of a plurality of various glass raw materials such as natural raw materials and chemical raw materials are weighed, and the composition of glass fibers obtained by spinning after melting is shown in Table 1 as a percentage by mass. It prepares so that it may become a composition shown by. The raw material mixture batch thus obtained is first put into a platinum rhodium crucible. Next, the platinum rhodium crucible charged with the raw material mixing batch is heated in the indirect heating electric furnace in the air atmosphere at the primary melting temperature for 5 hours, and the glass raw material mixing batch is subjected to a high temperature chemical reaction to obtain molten glass and did. In primary melting, in order to adjust the value of β-OH, attention was paid so that the atmospheric temperature, the humidity of the atmosphere, and the pressurizing conditions were also appropriate values. In addition, in order to make a molten glass into a homogeneous state, the molten glass was stirred using a heat-resistant stirring rod in the middle of heating and melting.

  The molten glass in a homogeneous state was roll-molded to obtain a film-like glass having a thickness of 1 mm. This film-like glass was pulverized with a ball mill to a particle size passing through a sieve having an opening of 5 mm to obtain a glass material. Moreover, when measuring glass physical property, the film forming thickness was changed as needed.

  This material is continuously supplied to a heat-resistant container maintained at a remelt temperature to perform secondary melting, and molten glass is continuously drawn out from 200 heat-resistant nozzles provided on the bottom surface of the heat-resistant container to obtain a single fiber diameter. A glass fiber having a fine count of 5 μm was spun. The obtained glass fiber was made into a glass yarn by a twisting machine and made into a plain weave glass cloth used for a printed wiring board using an air jet loom.

  Various evaluations were performed on the samples obtained by the above series of procedures. Table 1 shows the results obtained by the evaluation.

  The glass fibers shown in Table 1 were prepared so as to have a composition as indicated in advance, but the composition values of the obtained glass were further known using various analysis methods such as a fluorescent X-ray analyzer. The sample was analyzed as a standard, and it was confirmed that it had a predetermined composition.

SO ₃ component analysis of the powdered sample 1g was weighed in a platinum crucible _and mixed with Na 2 _CO 3 2 g, thereon covered with _Na 2 _CO 3 1g, 20 in an electric furnace set at 950 ° C. The alkali was melted for a minute. Thereafter, the contents of the platinum crucible were taken out with warm water (ultra pure water) and digested at 80 ° C. Then, it filtered with 5 types C filter paper, and made constant volume to 100 ml. 20 ml of the liquid was weighed, stirred for 10 minutes with 30 ml of ion exchange resin, filtered with 5 type A filter paper, adjusted to 100 ml, and then measured with an ion chromatograph to confirm the content of the SO ₃ component.

  The β-OH values in Table 1 were measured using a 1 mm thick film glass after primary melting. Although the difference from the secondary melting was also investigated in advance, since the secondary melting was not performed for a long time as the β-OH value changed, no difference was observed in the measured values. It measured using the apparatus which can measure the transmittance | permeability of the wavelength of infrared region, such as an infrared spectrophotometer.

  The linear thermal expansion coefficient was measured over a temperature range of 30 ° C. to 380 ° C. by a known thermal expansion measuring instrument that was calibrated using NIST SRM-731 and SRM-738 as standard samples with known thermal expansion coefficients. Average coefficient of thermal expansion. The lower the value of this linear thermal expansion coefficient, the smaller the expansion of the glass fiber, even when the temperature change is large. As a result, the temperature fluctuation when a printed wiring board using the glass fiber is mounted on an electronic device. It leads to increase the reliability related to.

In order to measure a temperature of 10 ^3.0 dPa · s indicating the high temperature viscosity of the molten glass (also referred to as spinning temperature), each glass sample crushed so as to have an appropriate size is put into an alumina crucible, Each value is calculated by interpolation of viscosity curves obtained by a plurality of measurements of each viscosity value measured based on the platinum ball pulling method after reheating and heating to a melt state.

  A dielectric constant ε and a dielectric loss tangent tan δ at a frequency of 1 MHz were measured using a glass sample piece processed to a size of 50 mm × 50 mm × 3 mm obtained after primary melting. Both surfaces of this glass sample piece having a thickness of 3 mm were polished with a polishing solution obtained by dissolving 1200th alumina powder in water. In the preliminary survey, no difference was observed in the measured values after primary melting and secondary melting. The measurement was performed by measuring at room temperature according to ASTM D150-87 and using a Yokogawa Hewlett Packard 4192A impedance analyzer. In addition, a plurality of cylindrical samples having different diameters were prepared by cutting. From values measured using these samples, values of a dielectric constant ε and a dielectric loss tangent tan δ at a frequency of 10 GHz were obtained by interpolation. Measurement of dielectric constant ε and dielectric loss tangent tan δ at a frequency of 10 GHz should be performed at room temperature by using an Agilent network analyzer according to a double-end short-circuited dielectric resonator method in accordance with JIS R1627: 1996. Obtained. The smaller the dielectric constant ε and the dielectric loss tangent tan δ, the smaller the heat loss of the printed wiring board when glass fiber is used for the purpose of constructing the printed wiring board. It becomes possible to suppress thermal deterioration.

  The volume electric resistance log ρ is obtained by measuring the electric resistance based on ASTM C657-78 while being heated to 150 ° C. The higher the value of the volume electrical resistance, the more stable electrical insulation performance can be achieved even with a printed wiring board on which high-density mounting is performed.

  The number of hollow fibers mixed first produced a glass cloth from a glass yarn, and this glass cloth was immersed in an immersion liquid adjusted to have the same refractive index as that of the glass, and a warp length of 100 mm over a cross width direction of 10 cm or more. The number of hollow fibers contained in the glass strand is measured by observing with a 50 × microscope. The number of measured hollow fibers is divided by the measured number of filaments and multiplied by 100,000 to obtain the number of hollow fibers per 100,000 glass filaments having a length of 100 mm. The smaller this value, the less dangerous the hollow fiber penetrates between the through holes of the printed wiring board, and it is less likely to cause conduction breakdown due to the penetration of plating solution into the hollow fiber, resulting in a stable quality printed wiring board. It becomes easy to get.

  The CV value of the fiber diameter is calculated by analyzing the fiber diameter obtained from the cross-sectional image of the glass strand using an image analyzer, measuring the fiber diameter of each filament, and deriving its standard deviation and average fiber diameter. did.

By the above test, sample No. which is an example of the present invention is obtained. 1 to sample no. Up to 5, the glass fiber obtained by secondary melting is SiO ₂ 74.6-76.5%, Al ₂ O ₃ 0.2-1.0% in terms of oxide% by mass, B ₂ O ₃ 19.1-10.5%, MgO 0.3-0.5%, CaO 0.4-0.6%, Li ₂ O 0.5-1.1%, Na ₂ O 1.4 _{~2.0%, K 2 O 0.8~1.1%} , a _{Li 2 O + Na 2 O +} K 2 O 3.3~3.5%, an SO ₃ content of 5~28ppm, β-OH The value ranged from 0.568 to 0.643. The performance of these samples is as follows: the linear thermal expansion coefficient is 31 to 33 × 10 ⁻⁷ / ° C., the spinning temperature is 1295 to 1335 ° C., the dielectric constant ε is 4.2 to 4.4, the dielectric loss tangent tan δ Of 0.001 to 0.002 and a dielectric constant ε of 1 GHz within a range of 4.2 to 4.4 and a dielectric loss tangent tan δ of 0.001 to 0.006. Furthermore, the volume electrical resistance of these samples at 150 ° C. was 12.8 to 13.1, the number of hollow fibers mixed per 100,000 filaments was 1 or less, and the CV value was within the range of 8 to 11%. From these facts, these sample Nos. 1 to sample no. Up to 5, glass fibers satisfying the requirements of the present invention.

  A particularly characteristic sample among the examples of the present invention will be described below.

Sample No. of Example The glass fiber No. 1 had the most Al ₂ O ₃ component of 1.0% by mass, but the linear thermal expansion coefficient was 33 × 10 ⁻⁷ / ° C., the spinning temperature was 1295 ° C., and the dielectric constant ε of 1 MHz. Is 4.4, the dielectric loss tangent tan δ is 0.002, the dielectric constant ε of 10 GHz is 4.4, and the dielectric loss tangent tan δ is 0.006, and the performance is satisfactory. The glass had a β-OH value of 0.643, an SO ₃ content of 5 ppm, and the number of hollow fibers was 0 per 100,000 filaments. Further, the CV value was as low as 11%, and the variation in the fiber diameter of the glass fiber was sufficiently small, so that the quality was stable.

In addition, sample No. The glass fiber of No. ₃ had a low B ₂ O ₃ component of 19.5% by mass, but had a linear thermal expansion coefficient of 32 × 10 ⁻⁷ / ° C., a spinning temperature of 1335 ° C., and a dielectric constant ε of 1 MHz. The dielectric constant ε was 4.3, the dielectric loss tangent was 0.001, the dielectric constant ε of 10 GHz was 4.3, and the dielectric loss tangent tan δ was 0.003. The performance was satisfactory. The glass had a β-OH value of 0.568, an SO ₃ content of 12 ppm, and the number of hollow fibers was determined as Sample No. As with 1, the number was 0 per 100,000 filaments. Further, the CV value was as low as 8%, the variation in the fiber diameter of the glass fiber was small, and the quality was stable.

Sample No. of Example The glass fiber of No. 5 had the largest Li ₂ O component of 1.1% by mass, while the Na ₂ O component was the smallest of 1.4% by mass, but the linear thermal expansion coefficient was 31 × 10 ^−7. / ° C, spinning temperature is 1315 ° C, dielectric constant ε of 1 MHz is 4.2, dielectric loss tangent tan δ is 0.001, dielectric constant ε of 10 GHz is 4.2, dielectric loss tangent tan δ is 0.001, and printed wiring Its performance was satisfactory when used on a board. The glass had a β-OH value of 0.585 and an SO ₃ content of 23 ppm. As with 1, the number was 100 per 100,000 filaments for a length of 100 mm. Further, the CV value was as low as 9%, the variation in the fiber diameter of the glass fiber was small, and the quality was stable as in the other examples.

  Next, as a comparative example, Sample No. 101 and sample no. As shown in Table 1, the glass according to 102 was also evaluated in the same procedure as in the example of the present invention, and a series of evaluations were performed. The results are shown below.

Sample No. of Comparative Example Since the glass fiber No. 101 has a high SO ₃ content of 70 ppm, the number of hollow fibers was as large as 20 per 100,000 filaments for a length of 100 mm in the glass fiber. The CV value was 14%, which was larger than that of the example.

Sample No. of Comparative Example Since the glass fiber No. 102 has an even higher SO ₃ content of 100 ppm, a β-OH value of 0.528 and a low viscosity reducing effect, the number of hollow fibers in this glass fiber is 100,000 for a length of 100 mm. The number of filaments was as large as 100 per filament. The CV value was also 15%, which was larger than that of the example.

As Example 2, Sample No. The glass of No. 3 was not melted in two stages, but a glass fusing was performed by a single melting using a tank melting furnace. Various conditions such as the temperature condition and the pressurizing condition in the furnace were adjusted in the same manner as in Example 1, and the glass composition was determined as Sample No. Adjusted to have a composition of 3, and prepared so that the SO ₃ content and β-OH value are also in an appropriate range, adjusted the melting conditions and the like so as to be the values in Table 1, and melted, A glass filament having a diameter of 4.5 μm was wound around a paper tube attached to a turret type winding device to obtain a glass fiber wound body. When the CV value of the obtained glass fiber was measured, it was 9%, which proved to be very stable. Moreover, the number of hollow fibers was excellent, with 0 pieces per 100,000 filaments for a length of 100 mm.

  Then, the glass strand is unwound from the obtained glass fiber wound body, cut to a length of 13 mm, cut into a glass chopped strand, dispersed in white water, and then lifted onto a mesh, conveyor In a state where it is randomly deposited on the sheet, a liquid binder is sprayed from above and the glass chopped strands are bonded to each other by curing the binder. Created. This glass paper also exhibited excellent performance with stable quality.

  Through a series of evaluations on the examples shown above, the glass fiber of the present invention is suitable as a fine count glass fiber used in a printed wiring board that realizes high-density mounting. Even in this case, it was clear that the number of non-hollow fibers mixed was small, the spinning property was excellent, and the product was of a stable quality due to high production efficiency. Moreover, it became clear that the glass fiber sheet-like material obtained from the glass fiber of the present invention exhibits excellent quality and performance as a printed wiring board application.

The glass fiber of the present invention exhibits its high performance when used as a printed wiring board. However, the present invention can be used as a package for electronic components, FRP structural materials, etc. If there is an application that requires performance that meets the requirements, it may be used.

Claims (9)

In mass percentage terms of _{oxides, SiO 2 70~80%, Al 2} O 3 0~2%, B 2 O 3 15~21.5%, 0~1% MgO, CaO 0~2%, Li 2 It contains a composition of O 0-2%, Na ₂ O 0-3%, K ₂ O 0-3%, Li ₂ O + Na ₂ O + K ₂ O 2-5%, and the content of SO ₃ is 50 ppm or less. Glass fiber characterized by   The glass fiber according to claim 1, substantially free of As, Sb, F, and Cl.   The glass fiber according to claim 1 or 2, wherein the β-OH value obtained by optical measurement is 0.55 / mm or more and 0.65 / mm or less.   The glass fiber according to any one of claims 1 to 3, wherein the number of hollow fibers per glass filament length of 100 mm is 3 pieces / 100,000 filaments or less.   The glass fiber according to any one of claims 1 to 4, which is used for a printed wiring board.   The glass fiber according to any one of claims 1 to 5, wherein the glass fiber is used as a glass cloth or a non-woven fabric to be combined with an organic resin material to form an organic resin composite material.   The glass according to any one of claims 1 to 6, wherein the glass is melted and spun so that a β-OH value obtained by optical measurement is 0.55 / mm or more and 0.65 / mm or less. A method for producing glass fiber, comprising producing a fiber.   A glass fiber comprising the glass fiber according to any one of claims 1 to 6 formed in a sheet shape and used in an application to form an organic resin composite material by being combined with an organic resin material. Sheet material. 9. The glass fiber sheet according to claim 8, wherein the glass fiber sheet is glass cloth or glass paper.