JP2016113339A - Glass fiber glass composition, glass fiber and method for producing glass fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a glass fiber composition which enables glass melting and spinning at a low temperature without special treatment such as crushing of raw material.SOLUTION: The composition comprises, by mass percentage in terms of oxide, SiO50-60%, AlO10-18%, BO3-6.3%, MgO 0-5%, CaO 18-28%, LiO+NaO+KO 0-2%, and F 0.001-0.2%.SELECTED DRAWING: None

Description

  The present invention relates to a glass composition for glass fiber used as a reinforcing material for a composite material, a glass fiber produced using the same, and a method for producing the same.

  Glass fibers (also referred to as glass fibers) used for composite materials with resins are generally produced as follows.

  First, the raw material mixture (referred to as a batch), which has been prepared and mixed to the desired composition, is put into a melting kiln, and the glass is heated by burner combustion of heavy oil or gas or by direct energization from the surface of the batch. Melting is advanced to gradually make a glass melt.

Subsequently, the molten glass is supplied to a molding apparatus called a bushing (also called a spinning furnace). The bushing is a device having a substantially rectangular appearance with a large number of nozzle parts (or orifice parts), and the temperature is controlled so that the viscosity of the molten glass at the tip part of the bushing nozzle is approximately 10 ³ dPa · s. (For example, patent document 1). The temperature at which the viscosity of the molten glass becomes 10 ³ dPa · s is called the molding temperature T _X, and the smaller the temperature difference ΔT _XL between T _X and the liquidus temperature _TL , the more the loss in the glass melt at the bushing nozzle tip. Permeability is likely to occur, and thread breakage is likely to occur. For this reason, it is preferable that ΔT _XL is larger.

  Thereafter, molten glass is spun to produce glass fibers. More specifically, molten glass supplied to the bushing is continuously drawn out from the tip of the bushing nozzle and rapidly cooled to form a filament shape, and a predetermined number of the glass melts to obtain glass fibers.

  The glass fiber manufactured in this way is called a long fiber, and is used for fiber reinforced plastic (FRP) which is a structural member such as a printed wiring board, a car, and an airplane.

JP 2007-39320 A

  When manufacturing glass fiber, the inside of the melting furnace for melting glass becomes a high temperature of 1500 ° C. or more, and enormous energy is required in the process from melting of glass to spinning. However, with the recent increase in awareness of global environmental problems, energy saving is required for the glass industry that uses a lot of energy. In addition, the higher the melting temperature, the greater the consumption of heavy oil, gas, and electricity, leading to higher manufacturing costs. Under such circumstances, efforts to melt glass at a lower temperature are required.

  Further, the higher the spinning temperature, the more likely the bushing is deformed and the life is shortened, resulting in an increase in manufacturing cost. For this reason, efforts to lower the spinning temperature are also required.

However, when melted at a low temperature, there is a problem that melting of a hardly soluble component such as SiO _{2 in} the batch is delayed and a heterogeneous melt is formed.

  In order to melt a highly homogeneous glass melt at a low temperature, there is a method in which a hardly soluble raw material is pulverized to reduce the particle size. However, this method has a problem that the manufacturing cost increases because a step of crushing the raw material is added to the glass manufacturing step. Also, the spinning temperature cannot be lowered by this method.

  An object of the present invention is to provide a glass fiber composition that can melt and spin glass at a low temperature without performing special treatment such as pulverization of raw materials.

  The present inventors have found that the above problem can be solved by introducing a predetermined amount of F (fluorine) into glass, and propose the present invention.

That is, the glass composition for glass fibers of the present invention is an oxide glass composition, and is expressed in terms of mass percentage in terms of oxide, SiO ₂ 50-60%, Al ₂ O ₃ 10-18%, B ₂ O ₃ 3. It is characterized by containing ˜6.3%, MgO 0-5%, CaO 18-28%, Li ₂ O + Na ₂ O + K ₂ O 0-2%, F 0.001-0.2%. Here, “Li ₂ O + Na ₂ O + K ₂ O” means the total content of Li ₂ O, Na ₂ O and K ₂ O.

  Since the glass composition for glass fiber of the present invention adopting the above configuration can reduce the high temperature viscosity, it can be melted and spun at a low temperature. Therefore, production with reduced energy consumption can be achieved, and products can be supplied at low cost.

In the present invention, in mass percent on the oxide basis, preferably further contains a _P 2 _O 5 _0.1~2%.

If the said structure is employ | adopted, liquid phase temperature can further be lowered | _hung and (DELTA) _TXL can fully be ensured.

  In this invention, it is preferable to contain SrO 0-2% and BaO 0-2% by the mass% of oxide conversion.

In the present invention, the temperature at which the viscosity of the glass becomes 10 ^2.0 dPa · s (melting temperature T _melt ) is preferably 1400 ° C. or lower.

  According to the said structure, it becomes possible to fuse | melt at low temperature.

In the present invention, the temperature at which the viscosity of the glass becomes 10 ^3.0 dPa · s (molding temperature T _X ) is preferably 1210 ° C. or lower.

  According to the said structure, it becomes possible to spin at low temperature.

In the present invention, the temperature difference ΔT _XL between the molding temperature T _X and the liquidus temperature _TL is preferably 100 ° C. or higher.

  According to the above configuration, stable spinning becomes easy.

  The glass fiber of the present invention comprises the above-described glass fiber composition. In the present invention, the “glass fiber” includes not only a bundle of a plurality of filaments but also monofilaments. The form is not limited.

  The glass fiber of the present invention is preferably provided in any form of chopped strands, yarns, and rovings.

Process for producing a glass fiber of the present invention has a glass composition, in weight percent oxide _{equivalent, SiO 2 50~60%, Al 2} O 3 10~18%, B 2 O 3 3.0~6.3% , MgO 0-5%, CaO 18-28%, Li ₂ O + Na ₂ O + K ₂ O 0-2%, F 0.001-0.2% of raw material batch prepared in a glass melting furnace It is characterized by melting and continuously drawing molten glass from the bushing into a fiber shape.

  Hereinafter, the reason for having prescribed | regulated the effect | action of the component which comprises glass, and its content as mentioned above about the glass composition for glass fibers of this invention is demonstrated. In addition, in description of the containing range of each component,% display points out the mass%.

SiO ₂ is one of the elements constituting the glass network. The content is 50-60%, preferably 50-58%, more preferably 52-56%. If the SiO ₂ content is too small, the structural strength of the glass is remarkably deteriorated and the mechanical strength required for the composite member using glass fibers cannot be satisfied. On the other hand, when the SiO ₂ content is too large, the high temperature viscosity increases. As a result, if an attempt is made to produce such a glass composition to be homogeneous with high efficiency by a melting method, the energy required for melting the glass increases and the production cost increases. In addition, when melting at a low temperature, a process such as pulverizing the raw material to make it fine is necessary, which also increases the manufacturing cost.

Al ₂ O ₃ is a component that suppresses crystal crystallization and phase separation in molten glass. The content of Al ₂ O ₃ is 10 to 18%, preferably 11 to 16%, more preferably 12 to 15%. If the content of Al ₂ O ₃ is too small, the liquidus temperature rises and ΔT _XL becomes small, which is not preferable. On the other hand, the Al ₂ O ₃ content is too large, the high temperature viscosity of the glass is increased, the melting property tends to deteriorate.

In B ₂ O ₃ is a glass network structure similarly to SiO _2, is a component that forms the skeleton, rather than increasing the high temperature viscosity of the molten glass as SiO _2, there is work to lower the high temperature viscosity rather . The content of B ₂ O ₃ is ₃ to 6.3%, preferably 4 to 6%, more preferably 4.5 to 5.5%. When B ₂ content of O ₃ is too small, it increased high temperature viscosity, the melting property tends to deteriorate. On the other hand, when the content of B ₂ O ₃ is too large, foreign glass such as scum is likely to be generated in the melting process.

MgO is a component that acts as a flux that makes it easy to melt glass raw materials, and at the same time is very effective in reducing high-temperature viscosity. It is a useful ingredient. The content of MgO is 0 to 5%, preferably 1 to 4%, more preferably 1.5 to 3%. If the MgO content is too large, the phase separation of the molten glass increases and ΔT _XL decreases, which is not preferable.

CaO is a component that lowers the high temperature viscosity together with MgO. The content of CaO is 18 to 28%, preferably 20 to 25%, more preferably 22 to 25%. When there is too little CaO content, the high temperature viscosity of glass will rise and a meltability will deteriorate easily. On the other hand, if the CaO content is more than 28%, the phase separation of the molten glass is increased, and ΔT _XL is decreased, which is not preferable.

Li ₂ O, Na ₂ O and K ₂ O which are alkali metal oxide components facilitate the production of a glass melt when heated in a mixed state of a plurality of glass raw materials to form a glass melt. It acts as a so-called flux. It also has the function of reducing the high temperature viscosity. The total amount of Li ₂ O, Na ₂ O and K ₂ O is 0 to 2%, preferably 0 to 1%, more preferably 0 to 0.8%. If the total amount of Li ₂ O, Na ₂ O, and K ₂ O is too large, the amount of alkali elution of the glass increases, the adhesive strength at the resin-glass interface decreases, and the mechanical strength of the printed wiring board tends to decrease. Therefore, it is not preferable.

F enhances the solubility of the raw material, also lower the high temperature viscosity, it is the melting temperature _{T melt,} spinning temperature T _x and liquidus temperature T _L significantly ingredients to lower. The content of F is 0.001 to 0.2%, preferably 0.01 to 0.18%, more preferably 0.02 to 0.15%, still more preferably 0.025 to 0.14%. Most preferably, it is 0.03 to 0.12%. When there is too little F content, the high temperature viscosity of glass will rise and a meltability will deteriorate. Furthermore, the energy required for glass melting increases. On the other hand, when there is too much F content, F discharged | emitted in an environment will increase and it is unpreferable environmentally.

  In addition to the above components, the glass composition for glass fiber of the present invention can further contain various components.

P ₂ O ₅ is an ingredient that has the effect of preventing the formation of fine crystal nuclei in the molten glass and can lower the liquidus temperature. However, if added in a large amount, the liquidus temperature is increased. The content of P ₂ O ₅ is preferably 0.1 to 2%, more preferably 0.1 to 1%, and still more preferably 0.1 to 0.5%. If the P ₂ O ₅ content is too small, the above effect cannot be obtained.

Further, SrO and BaO may be contained in order to reduce the high temperature viscosity. The SrO content is preferably 0 to 2%, more preferably 0.1 to 2%, and still more preferably 0.1 to 1.5%. Further, the content of BaO is preferably 0 to 2%, more preferably 0.05 to 1%, and still more preferably 0.05% to 0.5%. If the content of SrO or BaO is too large, the phase separation of the molten glass is increased, and ΔT _XL is decreased, which is not preferable.

Moreover, in order to reduce the foam in product glass, you may contain 1 or more types of fining agents. As the clarifier, for example, SO ₃ , Cl, SnO ₂ , Sb ₂ O ₃ , As ₂ O _{3 and the} like can be used. In this case, the total amount of standard fining agents added is within 0.5%.

Further, in order to improve chemical durability, high temperature viscosity, etc., in addition to the above components, 3% of each component such as Cr ₂ O ₃ , PbO, La ₂ O ₃ , WO ₃ , Nb ₂ O ₅ , Y ₂ O ₃ is added. May contain up to.

Moreover, the glass composition for glass fibers of this invention may contain, for example, H ₂ , CO ₂ , CO, H ₂ O, He, Ne, Ar, and N _{2 up} to 0.1% as impurities. Further, Pt, Rh, and Au may be contained up to 0.05% or less as impurities.

The glass composition for glass fiber of the present invention preferably has a melting temperature T _melt (temperature at which the viscosity of the glass becomes 10 ^2.0 dPa · s) is 1400 ° C. or lower, 1380 ° C. or lower, particularly 1360 ° C. or lower. If the melting temperature T _melt is too high, the glass must be melted at a high temperature, which increases the consumption of heavy oil, gas, and electricity, leading to an increase in manufacturing costs.

The glass composition for glass fibers of the present invention preferably has a molding temperature T _X (temperature at which the glass has a viscosity of 10 ^3.0 dPa · s) of 1210 ° C. or less, particularly 1190 ° C. or less. When T _X is too high, since the glass fiber must be spun at a high temperature occurs, bushing life tends shortened deformed, leading to increase in manufacturing cost.

The glass composition for glass fiber of the present invention preferably has a liquidus temperature _TL of 1080 ° C. or lower, particularly 1060 ° C. or lower. When _TL is too high, ΔT _LX becomes small and spinnability deteriorates. That is, devitrified substances are easily generated in the glass melt, and yarn breakage is likely to occur. The liquid phase temperature is about 120 × 20 × 10 mm in a platinum boat filled with the pulverized sample, placed in an electric furnace having a linear temperature gradient for 16 hours, and the temperature of the crystal precipitation determined by a microscope is the temperature of the electric furnace. It can obtain | require by the method of calculating from a gradient graph.

In the glass composition for glass fiber of the present invention, the temperature difference ΔT _XL between the molding temperature T _X and the liquidus temperature _TL is preferably 100 ° C. or higher, 110 ° C. or higher, particularly 120 ° C. or higher. If ΔT _XL is too small, spinnability deteriorates.

  The glass fiber of the present invention has the above composition and characteristics. The composition and characteristics are as described above, and the description is omitted here. The glass fiber of the present invention is preferably used in the form of chopped strand, yarn, roving or the like. The chopped strand is obtained by cutting a strand obtained by focusing glass monofilaments into a predetermined length. A yarn is a twisted strand. Roving is a combination of a plurality of strands wound in a cylindrical shape.

  Next, a method for producing the glass fiber production method of the present invention will be described.

  First, the prepared glass raw material batch is put into a glass melting furnace so as to have the above composition (and characteristics), and is vitrified, melted and homogenized. The composition is as described above, and the description is omitted here.

  Subsequently, molten glass is spun and formed into glass fibers. More specifically, molten glass is supplied to the bushing. The molten glass supplied to the bushing is continuously drawn out in filament form from a number of bushing nozzles provided on the bottom surface. Various processing agents are applied to the monofilaments drawn in this way, and glass fibers are obtained by focusing each monofilament.

  The glass fiber of the present invention thus formed is processed into chopped strands, yarns, rovings, etc. and used for various applications.

  Hereinafter, based on an Example, this invention is demonstrated in detail.

  Tables 1 and 2 show examples (sample Nos. 1 to 11) and comparative examples (sample No. 12) of the present invention.

  Each sample was prepared as follows.

  First, various glass raw materials, such as a natural raw material and a chemical raw material, were weighed and mixed so that it might become the glass composition in each table | surface, and a 500-g glass batch was produced. Next, this glass batch was put into a platinum rhodium alloy crucible and then melted at 1450 ° C. for 4 hours in an indirect heating electric furnace. Subsequently, the obtained molten glass was poured into a refractory mold and allowed to cool in air to obtain a massive glass sample. The glass sample thus obtained was subjected to various evaluations. The results are shown in each table.

As can be seen from the table, the sample No. 1 to 11 had a melting temperature T _melt of 1375 ° C. or lower. The spinning temperature T _X was 1184 ° C. or lower, and ΔT _XL was 109 ° C. or higher.

On the other hand, sample No. which is a comparative example. 12, the melting temperature _{T melt} is 1401 ° C., spinning temperature _{T X} is the 1220 ° C., melting at low temperature, it can be seen spinning is difficult.

The melting temperature T _melt (temperature at which the glass viscosity becomes 10 ^2.0 dPa · s) and the spinning temperature T _X (temperature at which the glass viscosity becomes 10 ^3.0 dPa · s) were carried out as follows. The massive glass sample was crushed to an appropriate size, and put into an alumina crucible so that bubbles were not caught as much as possible. Subsequently, the alumina crucible is heated, the sample is made into a molten state, the measured value of the viscosity of the glass at a plurality of temperatures is obtained by a platinum ball pulling method, the constant of Vogel-Fulcher formula is calculated, and the viscosity curve is created, The glass was measured by a method of calculating the temperature at which the viscosity of the glass becomes 10 ^3.0 dPa · s and the temperature at which the viscosity becomes 10 ^2.0 dPa · s.

The liquid phase temperature _TL is measured by filling a crushed sample in a platinum boat of about 120 × 20 × 10 mm and placing it in an electric furnace having a linear temperature gradient for 16 hours. Calculated from the temperature gradient graph of the electric furnace, this temperature was defined as the liquidus temperature _TL .

Claims (9)

It is an oxide glass composition, and it is SiO ₂ 50 to 60%, Al ₂ O ₃ 10 to 18%, B ₂ O _{3 3 to} 6.3%, MgO 0 to 5% in terms of oxide percentage. A glass composition for glass fiber, which contains CaO 18 to 28%, Li ₂ O + Na ₂ O + K ₂ O 0 to 2%, F 0.001 to 0.2%. The glass composition for glass fibers according to claim 1, further containing 0.1 to ₂ % of P ₂ O _{5 in} terms of mass% in terms of oxide. The glass composition for glass fibers according to claim 1 or 2, further comprising SrO 0 to 2% and BaO 0 to 2% in terms of mass% in terms of oxide. The glass composition for glass fibers according to any one of claims 1 to 3, wherein a temperature (melting temperature Tmelt) at which the glass has a viscosity of 10 ^2.0 dPa · s is 1400 ° C or lower. The glass composition for glass fibers according to any one of claims 1 to 4, wherein a temperature at which the glass has a viscosity of 10 ^3.0 dPa · s (molding temperature T _X ) is 1210 ° C or lower. Glass fiber glass composition according to any one of claims 1 to 5 temperature difference [Delta] T _XL the forming temperature T _X and the liquidus temperature T _L is equal to or is 100 ° C. or higher.   A glass fiber comprising the glass fiber composition according to any one of claims 1 to 6.   The glass fiber according to claim 7, wherein the glass fiber is provided in any form of chopped strand, yarn, and roving. As a glass composition, in weight percent oxide _{equivalent, SiO 2 50~60%, Al 2} O 3 10~18%, B 2 O 3 3~6.3%, 0~5% MgO, CaO 18~28% , Li ₂ O + Na ₂ O + K ₂ O 0-2%, F 0.001-0.2% of the raw material batch prepared so as to contain glass is melted in a glass melting furnace, and the molten glass is continuously drawn from the bushing And forming into a fiber shape.