JP2000247677A - Corrosion resistant glass fiber composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a corrosion resistant glass fiber which is free from B2O3 and F2 and easy to spin, has improved resistance to acids and is produced using inexpensive raw materials with good producibility. SOLUTION: The corrosion resistant glass fiber contains, by weight, 56-63% SiO2, 11-15% Al2O3, 15-25% CaO, 0.5-8% MgO, 0.5-8% ZnO, 1-12% MgO+ZnO, 0-0.5% TiO2, 0-1% Na2O, 0-1% K2O and 0.1-1.5% Na2O+K2O, and is substantially free from B2O3 and F2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a corrosion-resistant glass fiber having the same productivity as that of an E glass fiber and having the same mechanical and electrical properties and excellent in acid resistance and water resistance. .

[0002]

_2. Description of the Related Art Most of glass fibers currently used for fiber-reinforced resin products such as FRP are 52 to 56% by weight of SiO ₂ called E glass fiber and 12 to 1 of Al ₂ O ₃ .
6 _{wt%, B 2} O 3 _5~8 wt%, CaO 15 to 2
It is a glass fiber mainly containing 5% by weight. (Hereinafter, in the present invention,% means% by weight unless otherwise specified.) Most glass fibers which are currently produced worldwide even though glass fibers of this composition have already been manufactured for more than 50 years. Is made of E glass fiber because the devitrification temperature of the glass in its molten state is about 100 ° C. lower than the temperature suitable for spinning, and there is no trouble in spinning and the productivity is very good.

[0003]

However, E gala
Fiber has poor acid resistance and its use is expanding in FRP sewage.
Reinforcement for ducts, concrete to sewer pipes
Acid resistance is required for packaging and battery separators
Cannot be used in the field. For this reason, it is referred to as ECR.
Many compositions including acid-resistant glass fiber
Glass fiber has been developed, but compared to E-glass.
Problems such as difficult spinning and poor electrical properties
Further improvements are desired. In the present invention, the corrosion resistance is
A broader concept that includes acid resistance and water resistance. In addition, E
Lath fiber contains a large amount of B in the composition_TwoO_Three Containing glass
F to facilitate melting of the mixture_Two Contains ingredients
But B_Two O_Three Decrease in resource production, F _Two Environmental pollution countermeasures
Rising production prices have become a problem due to increased costs, etc.
You. The problem to be solved by the present invention is, specifically,
_Two O_Three , F_Two The spinning temperature of glass fiber is 1
300 ° C or lower, liquidus temperature 60 ° C or higher than spinning temperature
Developed a glass composition that is easy to spin with low acid resistance and water resistance
Excellent and mechanical and electrical properties are E glass fiber
It is to obtain glass fiber which is only.

[0004]

The corrosion resistant glass fiber of the present invention has the following composition. Component ratio _{(wt%) SiO 2 56~63 Al 2 O} 3 11~15 CaO 15~25 MgO 0.5~ 8 ZnO 0.1~ 8 MgO + ZnO less than _{1~12 TiO 2 0~ 0.5% Na 2} O 0 to 1 K ₂ O 0 to 1 Na ₂ O + K ₂ O 0.1 to 1.5 The total of these components is at least 99.0%. In addition, the composition including a trace amount of impurities contained in the raw material is included. Is 1
00%. This composition has a viscosity of 1000 poise, a temperature in the range of 1174-1297 ° C., and a viscosity of 100 poise.
It has a liquidus temperature at least 60 ° C. below the temperature of 0 poise. Thus, spinning is possible without devitrification despite high operating conditions.

[0005] With such a composition, the spinning temperature is 1300 ° C or less, and the liquidus temperature is 60 ° C lower than the spinning temperature.
By making the above lower, spinnability which greatly affects productivity was improved, and a composition having excellent acid resistance was able to be obtained. SiO ₂ is a component that improves the acid resistance of glass. If it is less than 56%, the acid resistance is not sufficient, and 63%
When the temperature exceeds the above range, the melting temperature increases and the liquidus temperature also increases, resulting in poor spinnability. Al ₂ O ₃ is a component that improves the water resistance of the glass and lowers the liquidus temperature. 11
%, The liquidus temperature increases and spinnability deteriorates. Fifteen
%, The water resistance is improved, but the melting temperature is too high. CaO is a component that improves the water resistance of the glass, reduces the viscosity of the glass, and improves the meltability. Fifteen
If it is less than 25%, the melting temperature becomes too high, and if it exceeds 25%, the liquidus temperature becomes high, the spinnability deteriorates and the dielectric constant deteriorates.

[0006] MgO is a component that lowers the viscosity of glass and improves the meltability. If less than 0.5%, no effect is obtained and 8
%, The liquidus temperature increases and spinnability deteriorates. Z
nO is a component that lowers the viscosity of the glass, improves the meltability, and improves the acid resistance. If it is less than 0.1%, the acid resistance will be poor, and if it exceeds 8%, the liquidus temperature will be high and the spinnability will be poor. In the present invention, in consideration of meltability and acid resistance, Mg
The total amount of O and ZnO is set to 1 to 12%. If it is less than 1%, the meltability deteriorates and the melting temperature increases, and if it exceeds 12%, the liquidus temperature increases and spinnability deteriorates. TiO ₂ is a component that improves the melting property, but gives an undesired color to the glass. An appropriate range is 0 to less than 0.5%. Na ₂
Alkali metal oxides such as O and K ₂ O are components that lower the viscosity of glass and improve the meltability. Na ₂ O + K
_{If 2} O is less than 0.1%, the melting temperature becomes high, and 1.5%
If it exceeds 300, the water resistance and the electrical properties deteriorate. In addition, TiO ₂ and Fe ₂ O usually inevitably contained as impurities of the raw material
₃ , SrO, etc. or Cr ₂ O ₃ or Zr
O ₂ or the like may be mixed about 1% or less, respectively.

In another preferred embodiment, Si
O ₂ , CaO, Al ₂ O ₃ , MgO, ZnO, MgO +
_ZnO, the amount of _{TiO 2, Na 2 O + K} 2 O is as follows. Component ratio _{(wt%) SiO 2 57.0~62.0 CaO 18.0~24.0 Al} 2 O 3 12.0~14.0 MgO 1.5~ 6.0 ZnO 1.5~ 6.5 _{MgO + ZnO 3.0~10.0 TiO 2 0 ~0.4} Na 2 O + K 2 O 0.1~0.9 this composition, the temperature of the viscosity of 1000 poise 1224～
It has a liquidus temperature in the range of 1290 ° C and a viscosity at least 70 ° C below a temperature of 1000 poise.

More preferred SiO ₂ , CaO, Al ₂ O
₃ , MgO, ZnO, MgO + ZnO, TiO ₂ , Na
The amount of ₂ O + K ₂ O is as follows. Component ratio _{(wt%) SiO 2 58.5~61.0 CaO 19.5~23.0 Al} 2 O 3 12.5~13.5 MgO 2.0~4.0 ZnO 2.0~5.5 MgO + ZnO 4.5-8.0 TiO ₂ 0-0.3 Na ₂ O + K ₂ O 0.1-0.6 More preferably, TiO ₂ is 0.3% by weight or less, more preferably 0.2% by weight. % By weight or less.

In one particularly preferred embodiment, the continuous fiber has the following composition. 59.55% of SiO ₂ , C
aO 20.71%, Al ₂ O ₃ 12.64%, Mg
O 2.53%, ZnO 3.77%, Na ₂ O 0.
_{33%, K 2 O 0.16%} , Fe 2 O 3 0.13
%, TiO ₂ 0.18%. This glass has a temperature of 1000 poise at 1260 ° C., a liquidus temperature of 1155 ° C., a difference between the two temperatures, and ΔT of 105 ° C.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION This glass fiber contains substantially B ₂
O ₃ and F ₂ are not contained. The term "substantially not contained" means that a trace is present in a very small amount even if it is contained, for example, an impurity is present in the raw material. The glass fiber of the present invention is manufactured by the same known method as the conventional glass fiber. As the glass fiber raw material, in addition to the raw materials used for known E glass fibers such as clay, silica sand, alumina, limestone, slaked lime, and dolomite, powdered ZnO is measured and mixed in the same manner as in a normal operation. The mixed raw material is put into a melting furnace, melted and clarified, and led to a bushing for producing a fiber attached to a lower portion of the foreheart. The temperature of the forehearth and the bushing is adjusted so that the molten glass has a viscosity suitable for spinning. The molten glass is drawn from a number of nozzle tips provided in the bushing, stretched at a high speed, provided with a sizing agent, and wound up.

[0011]

The features of the present invention will be described below with reference to examples.
In the present embodiment, the spinnability is easily estimated from the spinning temperature and the liquidus temperature as described in this specification. The difference (ΔT) was calculated and is shown in Tables 1 and 2 as data for determining the degree of difficulty. <Examples> Examples 1, 2, 3, and 4 are glass fiber compositions of the present invention, and raw materials were prepared so as to have the glass fiber compositions shown in Table 1. The mixed raw material was put in a platinum crucible and melted at 1500 ° C. for 8 hours to form a uniform molten glass, which was then poured onto a carbon plate and cooled to obtain a glass as a sample. The spinning temperature (the temperature at which the viscosity of the molten glass becomes 1000 poise) was measured by remelting the prepared glass in a platinum crucible and using a high-temperature rotational viscometer. The liquidus temperature (the temperature above which the crystal does not exist in the glass) is measured using a prepared glass having a diameter of about 500 to 100.
The powder was crushed into a powder of 0 μm, put into a platinum boat, left still in a furnace having a temperature gradient, kept for 12 hours, and the crystal generation position of the sample taken out was measured by a microscope.

The acid resistance is as follows. The glass of each Example is melted again in a platinum crucible, and a glass fiber having a diameter of 13 μm is spun.
The weight loss when immersed in a 10% by weight sulfuric acid solution heated for 5 hours was measured, and the ratio to the original fiber weight was calculated.

Water resistance was measured using the same glass fiber having a diameter of 13 μm as used in the acid resistance test.
g was immersed in distilled water heated to 96 ° C. for 100 hours, and the weight loss was measured to calculate the ratio to the original fiber weight.

<Comparative Example> Comparative Example 1 is a composition of a conventional E glass, Comparative Examples 2 to 4 are compositions outside the scope of the present invention, and Comparative Example 5 is a composition of an acid-resistant glass ECR glass. The same test as in the example was conducted, and the results are shown in Table 2. Compared with the E glass fiber of each example and the comparative example 1 and the ECR acid resistant glass fiber of the comparative example 5, the acid resistance is much higher than that of the E glass and has the same acid resistance as the ECR acid resistant glass fiber. I understand. The ECR glass is heavy use of expensive TiO2 raw materials, the composition of the present invention, since TiO ₂ is extremely small, there is a difference in significant performance in terms of raw material costs. Comparative Examples 2 to 4 are all similar to the composition of the present invention, but are not included in the scope of the claims. Comparative Example 2 has a high spinning temperature, and it is difficult to control the temperature of the bushing surface. The consumption of platinum alloy is large, the melting energy is also large and it is not economical. Comparative Example 3 had good spinnability but had poor acid resistance and contained a large amount of TiO ₂ , so that the glass was colored yellow. Comparative Example 4 is excellent in acid resistance, but has a small difference between the spinning temperature and the liquidus temperature and is difficult to spin.

[0015]

[Table 1]

[Table 2] ΔT (° C) = spinning temperature (° C)-liquidus temperature (° C) Acid resistance (%) and water resistance (%) = {(weight of fiber before test-weight of fiber after test) / weight of fiber before test} x 100

[0016]

According to the present invention, a glass fiber substantially free of B ₂ O ₃ and F ₂ can be produced without lowering the productivity by producing a glass fiber having the composition described in claim 1. In addition, it was possible to solve a difficult problem of improving corrosion resistance such as acid resistance. Also expensive T
It is economically effective because iO ₂ can be produced without using a very small amount as a raw material or blending it as a raw material.

Continued on the front page F-term (reference) 4G062 AA05 BB01 DA06 DB04 DC01 DD01 DE02 DE03 DF01 EA01 EB01 EB02 EC01 EC02 ED02 ED03 EE04 EF01 EG01 FA01 FA10 FB01 FB02 FC01 FD01 FE01 FF01 FG01 F01G01 F0101 HH05 HH07 HH09 HH11 HH13 HH15 HH17 HH20 JJ01 JJ03 JJ05 JJ07 JJ10 KK01 KK03 KK05 KK07 KK10 MM15 NN29 NN33 NN34 4L037 CS16 PA31 UA12

Claims (2)

[Claims] (1) 56-63% of SiO _{2 by} weight%, Al ₂
O ₃ 11-15%, CaO 15-25%, MgO
0.5-8%, ZnO 0.1-8%, MgO + ZnO
1 to 12%, TiO ₂ less than 0 to 0.5%, Na ₂
O 0-1%, K ₂ O 0-1%, Na ₂ O + K ₂ O
0.1 to 1.5% and substantially B ₂ O ₃ and F
_2. Corrosion-resistant glass fiber containing no ₂ . 2. The difference between the spinning temperature and the liquidus temperature is at least 6
The glass fiber composition according to claim 1, wherein the temperature is 0 ° C or higher.