JP2002154843A - Glass composition for glass fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a glass fiber having a high strength and a high elastic modulus, in which the working temperature range during the production of glass fiber is wide, the generation of bubbles at the time of devitrification of the glass composition is sufficiently reduced. To provide a possible glass composition for glass fibers. SOLUTION: This is a glass composition having a basic composition consisting of SiO ₂ , Al ₂ O ₃ and MgO, wherein SiO ₂ / A
l ₂ O ₃ is 2.35 to 3.40 by weight, and Al ₂ O ₃
/ MgO in a weight ratio of 1.25 to 2.30, and S
A glass composition for glass fibers, wherein the total weight of iO ₂ , Al ₂ O ₃ and MgO is 98% by weight or more based on the total weight of the glass composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a glass composition for glass fiber, a glass fiber comprising the glass composition for glass fiber, a glass fiber braid obtained by braiding the glass fiber,
The present invention relates to a glass fiber reinforced resin containing the glass fiber, and a printed wiring board provided with a layer made of the glass fiber reinforced resin.

[0002]

2. Description of the Related Art Glass fibers used for printed wiring boards and the like are required to have high strength. As a glass material for such high strength glass fibers, for example, about 4 to 25% by weight of MgO is used. The composition is essentially composed of added SiO ₂ and Al ₂ O ₃ , specifically, SiO ₂ 5 on a weight basis.
_{5~85%, Al 2 O 3 10~35} % , and MgO. 4 to
A glass (S glass) having a composition of 25% is known (Japanese Patent Publication No. 48-30125).

[0003]

The glass fiber made of S glass has the advantage of high strength, but when glass fiber is produced using this glass, bubbles are generated when the glass is devitrified. There was a problem that it was easy to do. When the bubble diameter of the bubbles generated at the time of devitrification is small, so-called hollow fibers in which the bubbles are contained in the glass fibers are generated, and the glass fibers containing the hollow fibers are reinforced fibers, for example, in a printed wiring board. When used, the insulation resistance was reduced, causing insulation failure. On the other hand, when the bubble diameter is large, there is a problem that the glass fibers are cut by the bubbles during spinning.

Further, it has been difficult to produce glass fibers from the viewpoint of 1000 poise temperature and liquidus temperature. Here, the term “1000 poise temperature” refers to a temperature at which the melt viscosity of the glass becomes 1000 poise, and the term “liquidus temperature” refers to a temperature at which crystal precipitation occurs first when the temperature of the molten glass is lowered. Generally, glass fibers can be efficiently produced when the glass is spun with the melt viscosity of the glass being around 1000 poise, and thus the 1000 poise temperature is a temperature used as an index during spinning. The liquidus temperature is a temperature that is an index of the uniformity of the molten state of the glass. The S glass has a liquid temperature close to the 1000 poise temperature, and therefore has a small working temperature range (a value obtained by subtracting the liquid phase temperature from the 1000 poise temperature), and has a very low temperature range in which glass fibers can be produced satisfactorily. There was a problem in the production of glass fibers that was narrow.

The present invention has been made in view of the above-mentioned problems of the prior art. In addition to the fact that the working temperature range during the production of glass fiber can be sufficiently widened, the present invention provides a method for reducing the devitrification of a glass composition. Glass for glass fiber, which can sufficiently reduce the generation of bubbles and can obtain glass fiber with high strength and high modulus of elasticity without cutting glass fiber or generating hollow fiber during spinning. It is intended to provide a composition.

The present invention also provides a glass fiber having a high strength and a high modulus of elasticity comprising the glass composition for a glass fiber, a glass fiber braid formed by braiding the glass fiber, a glass fiber reinforced resin containing the glass fiber, It is another object of the present invention to provide a low-permittivity printed wiring board including the glass fiber reinforced resin layer and having reduced insulation failure.

[0007]

Means for Solving the Problems The present inventors have achieved the above object.
As a result of intensive research to achieve
SiO_Two, Al_TwoO_ThreeAnd the ratio of MgO,
The first crystal formed during devitrification of glass
Phase) instead of Mullite but cordierite (C
ordierite) or tridymite
And that the generation of bubbles due to devitrification is drastically reduced.
I found a phenomenon that was not well known. And this knowledge
As a result of further research based on observations,
SiO _Two/ Al_TwoO_ThreeWeight ratio and Al_TwoO_Three/ MgO
By controlling the weight ratio of
Not only is it sufficiently reduced, but also during the production of glass fiber
Temperature range can be widened sufficiently, high strength and high elasticity
Found that it is also possible to obtain glass fibers with
Was.

Further, a glass fiber braid can be obtained by braiding such a glass fiber, and a glass fiber reinforced resin can be formed from the glass fiber. The inventors have found that a printed wiring board having a dielectric constant can be obtained, and completed the present invention.

That is, the glass composition for glass fiber of the present invention is a glass composition having a basic composition consisting of SiO ₂ , Al ₂ O ₃ and MgO, wherein SiO ₂ / Al ₂ O ₃
Is 2.35 to 3.40 by weight, and Al ₂ O ₃ / Mg
O is 1.25 to 2.30 in weight ratio, and Si
The total weight of O ₂ , Al ₂ O ₃ and MgO is at least 98% by weight based on the total weight of the glass composition.

In the glass composition for glass fibers, the weight ratio of SiO ₂ / Al ₂ O ₃ is 2.50 to 3.40.
It is preferable that Al ₂ O ₃ / MgO is 1.45 to 2.25 in weight ratio.

The present invention also provides a glass fiber comprising the above glass composition for glass fibers, a glass fiber braid comprising the above glass fibers braided, a glass fiber braid, At least one resin selected from the group consisting of a thermoplastic resin and a thermosetting resin, and a glass fiber reinforced resin comprising: a glass fiber reinforced resin layer made of the above glass fiber reinforced resin;
A printed wiring board comprising: a conductor layer bonded to an outermost layer of the glass fiber reinforced resin layer.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The glass composition for glass fiber of the present invention has a total weight of SiO ₂ , Al ₂ O ₃ and MgO of 98% by weight or more based on the total weight of the glass composition.
It is a glass composition having a basic composition of iO ₂ , Al ₂ O ₃ and MgO, and the weight ratio of each component satisfies the following conditions. SiO ₂ / Al ₂ O ₃ = 2.35 to 3.40 (1) Al ₂ O ₃ /MgO=1.25 to 2.30 (2)

A glass composition satisfying the above conditions will be described with reference to a composition diagram. FIG. 1 shows SiO ₂ , Al ₂ O ₃ and Mg
It is a composition figure showing the glass composition which consists of three components of O. The line A in FIG. 1 is a straight line satisfying the relationship of SiO ₂ / Al ₂ O ₃ = 2.35, and the line B is SiO ₂ / Al ₂ O ₃ =
It is a straight line that satisfies the relationship of 3.40. On the other hand, C line is Al
_A straight line satisfying the relationship of ₂ O ₃ /MgO=1.25,
The line is a line satisfying the relationship of Al ₂ O ₃ /MgO=2.30. Therefore, the area that satisfies the above conditions (1) and (2) is an area surrounded by the A-line, the B-line, the C-line, and the D-line (the area represented by I in FIG. 1).

The intersection of line A and line C in FIG.
Point X) is (SiO 2_Two, Al_TwoO _Three, MgO) = (5
6.63% by weight, 24.09% by weight, 19.28% by weight
%), And the intersection of line A and line D (in FIG. 1
Point Y) is (SiO_Two, Al_TwoO _Three, MgO) = (62.
09 wt%, 26.42 wt%, 11.49 wt%)
Points. Also, the intersection of line B and line C in FIG.
(Point Z in FIG. 1)_Two, Al_TwoO_Three, Mg
O) = (65.39% by weight, 19.23% by weight, 15.
38% by weight), and the intersection of line B and line D (FIG. 1).
At point W) is (SiO_Two, Al_TwoO_Three, MgO) =
(70.33% by weight, 20.68% by weight, 8.99% by weight
%). Therefore, the above (1) and
An area satisfying the condition (2) is surrounded by points X, Y, Z, and W.
It can be said that it is within the range to be performed.

It should be noted that each of the above points X, Y, Z, W
The weight% of the components is such that the glass composition for glass fibers of the present invention is
SiO contained_Two, Al_TwoO_ThreeAnd the total of MgO to 100
% Of the glass fiber of the present invention.
The fiberglass composition is SiO_Two, Al_TwoO_ThreeAnd other than MgO
(A total of less than 2% by weight can be contained).
If the actual SiO_Two, Al_TwoO_ThreeAnd MgO content
It will be different from the above numerical value. That is, the gas of the present invention
Glass composition for lath fiber is SiO_Two, Al_TwoO_ThreeAnd Mg
In addition to O, for example, Na_TwoO and Fe_TwoO_Three0.5
Weight percent, the actual gas at points X, Y, Z, W
SiO in glass composition for lath fiber _Two, Al_TwoO_ThreePassing
And MgO content is the value obtained by multiplying the above value by 0.995
Becomes

As described above, according to the findings newly found by the present inventors, SiO ₂ , Al ₂ O ₃ and MgO
The generation of bubbles due to the devitrification of the glass composition having the basic composition largely depends on the type of crystal (first phase of devitrification) formed at the time of devitrification. That is, when the devitrified initial phase is mullite (3Al ₂ O ₃ .2SiO ₂ ), bubbles are likely to be generated during devitrification, whereas the devitrified initial phase is cordierite (2MgO.2Al ₂ O ₃ .5SiO ₂ ) _{In the case of 2} ) or tridymite (SiO ₂ ), the formation of bubbles due to devitrification is drastically reduced.

The line D in FIG. 1 is based on the above findings. That is, the region (Al ₂ O ₃
/MgO>2.30), the devitrification initial phase of the glass composition is mullite, and bubbles are generated at the time of devitrification. However, the region on the left side of the D line (Al ₂ O ₃ / MgO).
In a region satisfying the relationship of ≦ 2.30), since the devitrified primary phase of the glass composition is cordierite or tridymite, the generation of bubbles upon devitrification is sufficiently reduced.

Although the present inventors do not wish to be bound by any theory, the change in bubble generation depending on the type of crystal is related to the shape of the crystal in the devitrified primary phase. It is considered something. It is considered that the bubbles generated at the time of devitrification are generated when the gas component originally dissolved in the molten glass component cannot be melted into the crystal formed by the devitrification. Further, it is presumed that there is also an influence of air or the like taken in when the glass raw material is melted and stirred. Mullite has a needle-like crystal shape, and when formed in large numbers upon devitrification, it overlaps with each other to form a network structure, so it is considered that it is difficult for the generated bubbles to escape from the glass composition. Can be On the other hand, since cordierite and tridymite are in a crystalline form, it is assumed that even if bubbles are generated, the cordierite and tridymite easily escape from the glass composition. Therefore, Al ₂ O ₃ /MgO≦2.30 so that the devitrified primary phase becomes cordierite and tridymite.
By doing so, the problem of generation of bubbles is solved.

However, if the value of Al ₂ O ₃ / MgO is too small, the physical properties of the formed glass fiber become insufficient. That is, the region on the left side of the line C in FIG. 1 (the region satisfying the relationship of Al ₂ O ₃ /MgO<1.25)
In this case, the tensile strength and the tensile modulus of the glass fiber become insufficient. In the region on the left side of the line C, a problem in the production of glass fibers also occurs. That is, in this region, the liquidus temperature, which is the temperature at which crystals first precipitate when the temperature of the molten glass is lowered, is lower than the 1000 poise temperature, so that the optimal 1000 poise for glass fiber production is obtained. If the temperature is adjusted, crystals will be present in the molten glass, making it virtually impossible to produce glass fibers at a temperature of 1000 poise. In such a case, it is necessary to heat the glass composition to a temperature equal to or higher than the liquidus temperature and spin the glass composition under the condition that the viscosity is very low, so that good glass fibers cannot be obtained. Therefore, from the viewpoint of the ratio of Al ₂ O ₃ and MgO in the glass composition,
Al ₂ O ₃ / MgO must be in the range of 1.25 to 2.30 by weight.

On the other hand, the area (S
In the glass composition of (iO ₂ / Al ₂ O ₃ <the region satisfying the relationship of 2.35), the 1000 poise temperature of the glass composition is much lower than the liquidus temperature. It is virtually impossible to produce glass fibers in a practical manner.

Further, the region (S) above the line B in FIG.
In the glass composition of the range satisfying the relationship of iO ₂ / Al ₂ O ₃ > 3.40), the 1000 poise temperature increases and the tensile modulus decreases. A high 1000 poise temperature means that it is necessary to heat and melt the glass composition at a higher temperature than usual in order to produce good glass fibers, so that the cost of producing glass fibers rises. Further, even if glass fibers are manufactured at a high manufacturing cost, only glass fibers having insufficient tensile modulus can be obtained. Therefore, it is not realistic to manufacture glass fibers from a glass composition in such a region. Therefore, from the viewpoint of the ratio of SiO ₂ to Al ₂ O ₃ in the glass composition, the weight ratio of SiO ₂ / Al ₂ O ₃ is 2.35 to 3.40.
Must be within the range.

From the above, it is possible to make the 1000 poise temperature sufficiently higher than the liquidus temperature by setting the glass composition in the region surrounded by the lines A, B, C and D in FIG. Therefore, the working temperature range at the time of glass fiber production becomes sufficiently wide, and furthermore, since the initial phase of devitrification can be cordierite or mullite, the generation of bubbles at the time of devitrification of the glass composition can be sufficiently reduced. Can,
It is possible to obtain a glass fiber having high strength and a high elastic modulus without spinning of the glass fiber and generation of the hollow fiber during spinning.

In the glass composition for glass fiber of the present invention, the weight ratio of SiO ₂ / Al ₂ O ₃ is 2.50 to 3.4.
It is preferably 0. Further, it is preferable that the weight ratio of Al ₂ O ₃ / MgO is 1.45 to 2.25. In the present invention, the weight ratio of SiO ₂ / Al ₂ O ₃ is 2.50.
It is more preferable that the weight ratio of Al ₂ O ₃ / MgO is 1.45 to 2.25. SiO
_By setting the weight ratio of ₂ / Al ₂ O ₃ and Al ₂ O ₃ / MgO to such a range, the working temperature range can be expanded, the generation of bubbles at the time of devitrification can be reduced, the cutting of glass fiber and hollow fiber can be performed. Prevention of generation and further enhancement of strength and elastic modulus can be further promoted. Further, in the present invention, Si
The total weight of O ₂ , Al ₂ O ₃ and MgO is preferably at least 99% by weight based on the total weight of the glass composition.

The glass composition for a glass fiber of the present invention comprises S
iO_Two, Al_TwoO_ThreeAnd MgO as the basic composition,
SiO_TwoRaw material, Al_TwoO_ThreeRaw materials and MgO raw materials
A small amount of other components may be contained. Accordingly
Therefore, considering the production of the actual glass composition, the present invention
The glass composition for glass fiber is SiO_Two, Al_TwoO_ThreeAnd M
Including components other than gO (less than 2% by weight in total)
Good. The glass fiber composition of the present invention contains
May be SiO_Two, Al_TwoO_ThreeAnd components other than MgO
CaO, Fe_TwoO_Three, Na_TwoO, TiO_Two, K_TwoO,
ZrO_Two, MoO _Two, Cr_TwoO_ThreeAnd the like.

The glass fiber of the present invention comprises the glass composition for glass fiber described above. The glass fiber in the present invention may take any form of a glass fiber monofilament, a glass fiber strand composed of a plurality of glass fiber monofilaments, and a glass fiber yarn obtained by twisting the glass fiber strand.
The fiber diameter of the glass fiber monofilament is, for example, 3 to
30 μm, and the glass fiber strand is:
The monofilaments can be obtained by, for example, bundling 50 to 800 monofilaments. Further, the glass fiber yarn is applied to the glass fiber strand, for example, 13 times / 25 m.
m or less. The glass fiber of the present invention may be provided as a wound body wound about 10 to 200 km around a paper or plastic core material, or a glass fiber cut into about 1 inch (glass fiber chopped strand or the like). ) May be provided.

The glass fiber of the present invention has a tensile strength of typically 4 GPa or more and a monofilament of 80 GPa.
It shows a tensile modulus of at least a. Such values of the tensile strength and the tensile elastic modulus are significantly higher than those of widely used glass fibers (glass fibers made of E glass).

The method for producing the glass fiber of the present invention includes:
Known methods such as a re-melting method and a direct melting method can be adopted, and according to these known methods, usually, a molten glass composition is drawn at high speed from hundreds to thousands of platinum nozzles. Fiberizes the glass composition.

The glass fiber braid of the present invention is obtained by braiding the above glass fibers. Here, the braid means that glass fibers are knitted, braided, or the like so as to be entangled with each other or to be piled up, and the braided material is obtained by braiding. In the present invention, the glass fiber braid is a glass fiber fabric,
It may have any mode such as a glass fiber knit, a glass fiber braid, a glass fiber nonwoven fabric, and the like.

The glass fiber reinforced resin of the present invention contains the above glass fiber and at least one resin selected from the group consisting of a thermoplastic resin and a thermosetting resin. The glass fiber in the glass fiber reinforced resin of the present invention includes the above glass fiber braid in addition to the above glass fiber. Examples of the thermoplastic resin in the glass fiber reinforced resin of the present invention include polyamide (nylon), polyacetal, polycarbonate, polyvinyl chloride, ABS, polysulfone, polyethylene, polypropylene, polystyrene, (meth) acrylic resin, fluororesin, and saturated polyester resin. And examples of the thermosetting resin include unsaturated polyester resins, epoxy resins, and melamine resins. When the glass fiber reinforced resin contains a thermosetting resin, the glass fiber reinforced resin of the present invention includes, in addition to the glass fiber reinforced resin in which the thermosetting resin is completely cured,
It also includes a prepreg in which a thermosetting resin is in a semi-cured state. The glass fiber reinforced resin of the present invention may contain additives such as a low shrinkage agent, a flame retardant, a flame retardant auxiliary, a plasticizer, an antioxidant, an ultraviolet absorber, a colorant, a pigment, and a filler, if necessary. May be contained.

As a method for producing a glass fiber reinforced resin containing a glass fiber and a thermoplastic resin, a known method such as a stampable sheet molding method can be adopted, and a glass fiber reinforced resin containing a glass fiber and a thermosetting resin can be used. A known method such as a hand lay-up method, a spray-up method, a resin transfer method, a sheet molding compound method (SMC method) and the like can be adopted as a method for producing the compound.

The printed wiring board of the present invention comprises a glass fiber reinforced resin layer made of the above glass fiber reinforced resin, and a conductor layer joined to the outermost layer of the glass fiber reinforced resin layer. The glass fiber reinforced resin used for the printed wiring board of the present invention preferably contains the glass fiber of the present invention and a thermosetting resin, and the thermosetting resin is preferably a cured product of an epoxy resin. In addition, examples of the conductor layer include a conductor layer made of copper, silver, gold, or the like. The printed wiring board of the present invention contains glass fibers made of the above-described glass composition of the present invention, and the glass fibers have no defects such as the incorporation of bubbles, so that insulation failure is reduced. become. Therefore,
The printed wiring board of the present invention can be suitably used for home electric appliances, communication information equipment, and the like.

[0032]

Hereinafter, preferred embodiments of the present invention will be described in more detail, but the present invention is not limited to these embodiments.

(Examples 1 to 10) Glass raw materials were prepared so as to have the composition shown in Table 1, and the raw materials were placed in a platinum crucible.
The mixture was melted with stirring at 1600 ° C. for 8 hours in an electric furnace. Next, the molten glass was poured onto the carbon plate,
Glass compositions for glass fibers (glass cullet) of Examples 1 to 10 were produced. Upon slow cooling on the carbon plate, it was visually observed whether or not bubbles were generated when the glass composition for glass fiber was devitrified. Further, a crystal (first phase of devitrification) formed first at the time of devitrification was collected, and the crystal structure of the first phase of devitrification was identified by X-ray diffraction using Geigerflex manufactured by Rigaku Corporation. Further, Examples 1 to 1
Optical micrographs (magnification: 40 times) of the initial phase of devitrification of 0 were taken and are shown in FIGS. Further, using a glass cullet obtained by slow cooling, the following methods were used to measure the 1000 poise temperature, liquidus temperature, working temperature range, tensile strength, tensile modulus, coefficient of thermal expansion, and dielectric constant.

Table 1 summarizes the presence / absence of bubbles at the time of devitrification, the crystal structure of the initial phase of devitrification, and the measurement results of the above characteristics.
Table 1 shows the SiO 2 in each of Examples 1 to 10.
₂ / Al ₂ O ₃ (weight ratio) and Al ₂ O ₃ / MgO (weight ratio) are also described. In the glass compositions for glass fibers of Examples 1 to 10, SiO ₂ , Al ₂ O ₃ and MgO were used.
The composition diagram of the three components is shown in FIG. FIG. 2 shows line A, line B, line C, and line D in the same manner as in FIG. 1, and the composition is shown so that the initial phase of devitrification is cordierite, tridymite, or mullite.

[0035]

[Table 1]

[1000 poise temperature] A glass cullet was melted, and a temperature (° C.) showing 1000 poise was measured by a high-temperature rotational viscometer (manufactured by Shibaura System Co., Ltd.). [Liquid phase temperature] Part of the glass cullet is 297 to 500 µ
m and placed in a platinum boat. This platinum boat was placed in an electric furnace set at various temperatures (the set temperature was 1300
~ 1600 ° C) and kept for 14 hours,
After cooling, the presence or absence of devitrification was observed with a microscope, and the set temperature of the electric furnace where devitrification was observed was defined as the liquidus temperature. [Working temperature range] The working temperature range (° C) was defined as the value obtained by subtracting the liquidus temperature from the 1000 poise temperature obtained as described above.

[Tensile Strength and Tensile Modulus] Monofilament glass fibers were obtained using a one-hole platinum bushing at a temperature of 1460 to 1550 ° C. and a spinning speed of 1100 m / min. The obtained monofilament was cut into a length of 25 cm to obtain a sample for measuring tensile strength. This sample was placed along the length of the monofilament in a size of 2.5 cm × 1 c.
The paperboard was mounted on a paperboard having four m openings, the edges of the paperboard were cut out, and the diameter of the sample was measured with a laser outer diameter measuring instrument. The monofilament was bonded between the openings of the paperboard, cut off at each opening, and the tensile strength (GPa) and tensile modulus (GPa) of the 2.5-cm monofilament were measured using Tensilon UTM. The values were defined as the tensile strength and tensile modulus of the monofilament. [Coefficient of thermal expansion] Slowly cooled glass cullet is 14 mm x 8
A sample polished to a size of 5 mm x 5 mm was used as a sample.
nical Analyzer (TM-7000, manufactured by Vacuum Riko Co., Ltd.)
) Was used to measure the coefficient of thermal expansion. [Dielectric constant] An LCR meter (manufactured by Yokogawa-Hewlett-Packard Co., Ltd.) obtained by optically polishing both sides of a slowly cooled glass cullet to a diameter of 45 mm and a thickness of 2 mm.
HP4284A) at a frequency of 1 MH at room temperature.
The dielectric constant at z was measured.

(Comparative Examples 1 to 11) Glass raw materials were prepared so as to have the compositions shown in Table 2, and in the same manner as in Examples 1 to 10, the glass compositions for glass fibers of Comparative Examples 1 to 11 (glass cullet). Was prepared. In addition, in the same manner as in Examples 1 to 10, optical micrographs of the initial phase of devitrification of Comparative Examples 1 to 11 were taken (FIGS. 13 to 23). The crystal structure of the phase, 1000 poise temperature, liquidus temperature, working temperature range, tensile strength, tensile modulus, coefficient of thermal expansion, and dielectric constant were measured. Comparative Examples 1, 5, 6, and 7
And 8 are compositions corresponding to Examples 1, 3, 5, 6, and 7 in JP-B-48-30125.

Table 2 summarizes the measurement results. Table 2 shows that SiO ₂ / Al ₂ O _{3 in} each of Comparative Examples 1 to 11 are shown.
(Weight ratio) and Al ₂ O ₃ / MgO (weight ratio) are also described. FIG. 2 shows the compositions (SiO ₂ , Al ₂ O ₃ and M) of Comparative Examples 1 to 11 in the same manner as in Examples 1 to 10.
gO) are displayed so that the devitrified primary phase is cordierite, tridymite, or mullite.

[0040]

[Table 2]

Optical micrographs of the devitrified initial phase in Examples 1 to 10 (FIGS. 3 to 12) and optical micrographs of the devitrified initial phase in Comparative Examples 1 to 6 and 8 (FIGS. 13 to 18 and 20)
As is evident from the comparison with Al ₂ O ₃ / MgO ≦
In the glass fiber glass compositions of Examples 1 to 10 satisfy the relationship of 2.30, a cordierite or tridymite devitrification first phase particulate, whereas not observed formation of bubbles, Al ₂ In the glass fiber compositions for glass fibers of Comparative Examples 1 to 6 and 8 in which O ₃ /MgO>2.30, the initial phase of devitrification is acicular mullite, and many of these overlap to form a network-like structure. And foam is mixed.

[0042] In Comparative Examples 7 and 10 is Al ₂ O ₃ /MgO<1.25, although devitrification primary phase, as shown in FIGS. 19 and 22 do not show the occurrence of bubbles is cordierite, Al ₂ Tensile strength and tensile modulus are inferior to those of Examples 1 to 10 in which O ₃ /MgO=1.25 to 2.30, and 1000 poise temperature is lower than liquidus temperature.
Production of glass fibers is difficult because the working temperature range is negative.

SiO_Two/ Al_TwoO_ThreeComparisons> 3.40
In Example 9, as shown in FIG.
Although it is a unit and no bubbles are seen,_Two/ A
l_TwoO _Three= 2.35 to 3.40 compared with Examples 1 to 10
All have particularly poor tensile modulus values. In addition, 1
Glass polish temperature
Disadvantageous in that respect. In addition, SiO_Two/ Al_TwoO_Three<
In Comparative Example 11 of 2.35, as shown in FIG.
The initial phase of devitrification is cordierite, and no bubbles are seen
However, 1000 poise temperature is much higher than liquidus temperature
Low and not realistic from an industrial glass fiber production perspective.
No. Comparative Examples 5 and 6 were made of SiO 2 similarly to Comparative Example 11._Two/ A
l_TwoO_Three1000 poise because it is in the area of <2.35
The temperature is much lower than the liquidus temperature.

SiO ₂ / Al ₂ O ₃ = 2.35 to 3.4
0 and Al ₂ O ₃ /MgO=1.25 to 2.30, the glass compositions for glass fibers of Examples 1 to 10 did not generate bubbles at the time of devitrification, and had a 1000 poise temperature. The working temperature range is wide because it is sufficiently higher than the liquidus temperature. Further, since the glass fibers of Examples 1 to 10 show a tensile strength of 4 GPa or more and a tensile elasticity of 80 GPa or more, they are also excellent in terms of strength and elastic modulus. Therefore, a glass fiber braid free from defects due to bubbles can be obtained from such glass fibers, and a glass fiber reinforced resin having excellent strength can be produced. Further, as shown in Table 1,
Since the glass compositions for glass fibers of Examples 1 to 10 have a small coefficient of thermal expansion and a low dielectric constant, a printed wiring board made of a glass fiber reinforced resin containing this glass fiber is required to have high insulating properties and a low dielectric constant. It can be particularly suitably used for home electric appliances, communication information devices, and the like.

[0045]

As described above, according to the present invention,
In addition to sufficiently widening the working temperature range during glass fiber production, the generation of bubbles during devitrification of the glass composition can be sufficiently reduced, and cutting and hollowing of glass fibers during spinning. It is possible to provide a glass composition for a glass fiber, which can obtain a glass fiber having a high strength and a high elastic modulus without producing a fiber. Further, high-strength and high-modulus glass fibers made of the glass composition for glass fibers, a glass fiber braid formed by braiding the glass fibers, a glass fiber reinforced resin containing the glass fibers, and the glass fiber reinforced resin It is possible to provide a low-permittivity printed wiring board having a layer and reduced insulation failure.

[Brief description of the drawings]

FIG. 1 is a composition diagram showing a glass composition comprising three components of SiO ₂ , Al ₂ O ₃ and MgO.

FIG. 2 shows SiO ₂ , Al ₂ O ₃ and M in the glass fiber compositions of Examples 1 to 10 and Comparative Examples 1 to 11.
FIG. 3 is a composition diagram of three components of gO.

FIG. 3 is an optical micrograph of a first phase of devitrification in the glass composition for glass fibers of Example 1.

FIG. 4 is an optical micrograph of a first phase of devitrification in a glass composition for glass fibers of Example 2.

FIG. 5 is an optical micrograph of a devitrification initial phase in the glass composition for glass fibers of Example 3.

FIG. 6 is an optical micrograph of a first phase of devitrification in a glass composition for glass fibers of Example 4.

FIG. 7 is an optical micrograph of the first phase of devitrification in the glass composition for glass fibers of Example 5.

FIG. 8 is an optical micrograph of a devitrification first phase in the glass composition for glass fibers of Example 6.

FIG. 9 is an optical micrograph of a first phase of devitrification in the glass composition for glass fibers of Example 7.

FIG. 10 is an optical micrograph of the first phase of devitrification in the glass composition for glass fibers of Example 8.

FIG. 11 is an optical microscope photograph of a devitrified first phase in the glass composition for glass fibers of Example 9.

FIG. 12 is an optical micrograph of a devitrification first phase in the glass composition for glass fibers of Example 10.

FIG. 13 is an optical micrograph of a first phase of devitrification in the glass composition for glass fibers of Comparative Example 1.

FIG. 14 is an optical micrograph of a devitrification initial phase in the glass composition for glass fibers of Comparative Example 2.

FIG. 15 is an optical micrograph of a devitrification initial phase in the glass composition for glass fibers of Comparative Example 3.

FIG. 16 is an optical micrograph of a devitrified first phase in the glass composition for glass fibers of Comparative Example 4.

FIG. 17 is an optical micrograph of a devitrified first phase in the glass composition for glass fibers of Comparative Example 5.

FIG. 18 is an optical microscope photograph of a devitrification first phase in the glass composition for glass fibers of Comparative Example 6.

FIG. 19 is an optical micrograph of a devitrification first phase in the glass composition for glass fibers of Comparative Example 7.

FIG. 20 is an optical micrograph of a devitrified first phase in a glass composition for glass fibers of Comparative Example 8.

FIG. 21 is an optical micrograph of a devitrification initial phase in the glass composition for glass fibers of Comparative Example 9.

FIG. 22 is an optical micrograph of a devitrification initial phase in the glass composition for glass fibers of Comparative Example 10.

FIG. 23 is an optical micrograph of a first phase of devitrification in a glass composition for glass fibers of Comparative Example 11.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) D04B 21/00 D04B 21/00 B 4L048 D04C 1/02 D04C 1/02 D04H 1/42 D04H 1/42 B // C08L 101: 00 C08L 101: 00 F term (reference) 4F072 AA04 AA07 AA08 AB09 AB30 AL13 4G062 AA05 BB06 DA06 DB04 DC01 DD01 DE01 DF01 EA01 EB02 EC01 ED03 ED04 EE02 EF01 EG01 FA01 FA01 F01 FF01 FC01 FD01 FC01 FF01 FL01 GA01 GB01 GC01 GD01 GE01 HH01 HH03 HH05 HH07 HH09 HH11 HH12 HH13 HH15 HH17 HH20 JJ01 JJ03 JJ05 JJ07 JJ10 KK01 KK03 KK05 KK07 KK10 MM16 MM27 NN33 4L002 AAA A4A01 A04 A01 A04 A01 A04 A01 A00 A00 FA00A03 A04 A00 A00 FA00 AC09 AC11 AC14 CA03 CA06 DA43

Claims (7)

[Claims] 1. A glass composition having a basic composition comprising SiO ₂ , Al ₂ O ₃ and MgO, wherein SiO ₂ / A
l ₂ O ₃ is 2.35 to 3.40 by weight, and Al ₂ O ₃
/ MgO in a weight ratio of 1.25 to 2.30, and S
A glass composition for glass fibers, wherein the total weight of iO ₂ , Al ₂ O ₃ and MgO is 98% by weight or more based on the total weight of the glass composition. _{2. The} weight ratio of SiO ₂ / Al ₂ O ₃ is 2.50.
The glass composition for glass fibers according to claim 1, wherein 3. The weight ratio of Al ₂ O ₃ / MgO is 1.45 to 1.45.
The glass composition for glass fibers according to claim 1 or 2, wherein the composition is 2.25. 4. A glass fiber comprising the glass composition for a glass fiber according to claim 1. 5. A glass fiber braid comprising the glass fiber according to claim 4 braided. 6. A glass fiber reinforced resin comprising the glass fiber according to claim 4, and at least one resin selected from the group consisting of a thermoplastic resin and a thermosetting resin. 7. A printed wiring board comprising: a glass fiber reinforced resin layer made of the glass fiber reinforced resin according to claim 6; and a conductor layer bonded to an outermost layer of the glass fiber reinforced resin layer. .