CA2375719C - Glass fiber composition - Google Patents
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- CA2375719C CA2375719C CA002375719A CA2375719A CA2375719C CA 2375719 C CA2375719 C CA 2375719C CA 002375719 A CA002375719 A CA 002375719A CA 2375719 A CA2375719 A CA 2375719A CA 2375719 C CA2375719 C CA 2375719C
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C13/00—Fibre or filament compositions
Abstract
The present invention provides a glass fiber composition comprising: 52 to 62 percent by weight SiO2, 0 to 2 percent by weight Na2O, 16 to 25 percent by weight CaO, 8 to 16 percent by weight Al2O3, 0.05 to 0.80 percent by weight Fe2O3, 0 to 2 percent by weight K2O, 1.7 to 2.6 percent by weight MgO, 0 to 10 percent by weight B2O3, 0 to 2 percent by weight TiO2, 0 to 2 percent by weight BaO, 0 to 2 percent by weight ZrO2, and 0 to 2 percent by weight SrO, and further including at least one material selected from the group consisting of: 0.05 to 1.5 percent by weight Li2O, 0.05 to 1.5 percent by weight ZnO, 0.05 to 3 percent by wight MnO, and 0.05 to 3 percent by weigt MnO2, wherein the glass composition has a forming temperature of no greater than 2280 °F based on an NIST714 reference standard and a liquidus temperature of no greater than 2155 °F. In one nonlimiting embodiment of the invention, the SiO2 content is 57 to 59 percent by weight, the Na2O content is up to 1 percent by weight, the CaO content is 22 to 24 percent by weight, the Al2O3 content is 12 to 14 percent by weight, the Fe2O3 content is up to 0.4 percent by weight, and the K2O content is up to 0.1 percent by weight, and the composition includes at least one material selected from the group consisting of: 0.2 to 1 percent by weight Li2O, 0.2 to 1 percent by weight ZnO, up to 1 percent by weight MnO, and up to 1 percent by weight MnO2.
Description
GLASS FIBER COMPOSITION
Background of the invention 1. Field of the Invention The present invention relates to glass compositions for making glass fibers; and more particularly to glass compositions having lowered liquidus and forming temperatures.
Background of the invention 1. Field of the Invention The present invention relates to glass compositions for making glass fibers; and more particularly to glass compositions having lowered liquidus and forming temperatures.
2. Technical Considerations The most common glass composition for making continuous glass fiber strands for textiles and glass fiber reinforcements is "E" glass. The requirements as to what type of composition constitutes an E-glass composition are included in ASTM D578-98. An advantage of using E-glass is that its liquidus temperature is well below its forming temperature, i.e.
typically greater than 100°F (56°C) and generally between 1'50°F (83°C} to 200°F (711 °C}. As used herein, the terms "forming temperature"
and "TFORM"
mean the temperature of the,glass at which the viscosity of the glass is log 3, or 1000 poise, and the terms "liquidus temperature" and "T~,Q" mean the temperature at which solid phase (crystals) and liquid phase (melt) are in equilibrium. The difference between TFORnn and TL,Q, referred to herein as "delta T" or "OT", is a common measure of the crystallization potential of a given melt composition. In the glass fiber forming industry, DT is typically maintained at a temperature of at least 90°F (50°C) in order to prevent devitrification of the molten glass in the bushing area of a glass fiber forming operation.
Boron and fluorine containing glass were developed to meet these operating conditions. More specifically, the boron and fluorine were included in the glass batch materials to act as fluxes during the glass melting operation: However; these materials are volatilized during melting and boron and fluorine emissions are released to the atmosphere. Since boron and fluorine are considered pollutants, these emissions are closely controlled by environmental regulations, which; in turn, requires careful control of the furnace operations and the use of expensive pollution control equipment. tn response to this, low boron and/or low fluorine E-glasses were developed. As used herein, "low boron" means that the glass composition is no greater than 5 weight percent boron, and preferably boron-free and "low fluorine"means that the glass composition is no greater than 1 weight percent fluorine, and preferably is fluorine-free.
For example, U.S. Patent No. 3,929,497 disctoses a boron-tree and fluorine-free glass composition containing titanium dioxide in the range of 0.5 to 5 percent by weight and Fe2G3 in the range of 5 to 15 percent by weight.
U.S: Patent No. 4,199,364 discloses a boron-free and fluorine-free glass composition that contains Li20 in the range of 0.1 to 1.5 percent by weight and may also include barium oxide. The liquidus temperature of the compositions is over 2200°F.
U.S. Patent No. 4,542,106 discloses a boron-free and fluorine-free glass composition that contains 1 to 5 percent by weight Ti02. The fibers also have a seed count of 5 seeds or less per cubic centimeter of glass and an electrical leakage value of 2.8 nanoamperes or less.
U.S. Patent No. 5,789,329 discloses a boron-free and fluorine-free glass composition that contains up to 0.9 percent by weight Ti02 and has a DT of at least 100°F (56°C).
For additional information concerning glass compositions and methods for fiberizing the glass composition, see K: Loewenstein, The Manufacturina Technolo4y of Continuous Glass Fibres, (3d Ed. 1993) at pages 30-44, 47-60, 115-122 and 126-135, and F. T. Walienberger (editor), Advanced inorganic Fibers: Processes. Structures, Properties. Replications, (2000) at pages 81-102 and 129-168.
Because the actual fiber forming operation is conducted at high temperatures, there are high energy costs associated with its production. in addition, the high temperatures accelerate the degradation of the refractory used in the glass melting furnace as well as the bushings used to form the fbers. The bushings include precious metals that cannot be recovered from the glass as the bushings corrode. It would be advantageous to produce the glass fibers at the lowest possible forming and liquidus temperatures so as to reduce the energy costs and thermal load on the furnace refractory and bushings, while at the same time provide the DT required to ensure an uninterrupted glass fiber forming, operation. Reducing the forming and liquidus temperatures of the glass compositions can also result in environmental benefits, such as but not limited to, a reduction in the amount of fuel required to generate the energy necessary for the fiber forming operation, as well as a reduction in the flue gas temperature. In addition,' it would be advantageous if the glass compositions are !ow fluoride andlor low boron compositions, and preferably are fluorine-free arydlor boron-free, so as to reduce or eliminate the environmental pollutants associated with these materials.
Summary of the invention The present innovation provides a glass fiber composition comprising:
52 to 62 percent by weight Si02, '0 to 2 percent by weight Na20, 16 to 25 percent by weight CaO, 8 to 16 percent by weight A1203, 0.05 to 0.80 percent by weight Fe203, 0 to 2 percent by weight K20, 1.7 to 2.9 percent by weight MgO; O to 10 percent by weight B203, 0 to 2 percent by weight Ti02, 0 to 2 percent by weight BaO, 0 to 2 percent by weight Zr02, and'0 to 2 percent by weight SrO, wherein the glass composition has a forming.temperature of no greater than 2280°F based on an NIST 714 reference standard and a liquidus temperature of no greater than 2155°F. In one noniirniting embodiment of the invention, the glass fiber composition . further includes at least one material selected from the group consisting of: 0.05 to 1.5 percent by weight Li20, '0.05 to 1.5 percent by weight ZnO, 0:05 to 3 percent by weight MnO, and 0.05 to 3 percent by weight Mn02.
The present invention also provides a glass fiber composition -consisting essentially of: 52 to 62 percent by weight Si02, 0 to 2 percent by weight Na20, 16 to 25 percent by weight CaO, 8 to 16 percent by weight 9 0 A1203, 0.05 to 0.80 percent by weight Fe203, O to 2 percent by weight KZO;
2.2 to 2.9 percent by weight MgO, 0 to 10 percent by weight 823, 0 to 2 percent by weight Ti02, 0 to 2 percent by weight BaO, 0 to 2 percent by weight Zr02, and O to 2 percent by weight SrO, wherein the glass composition has a forming temperature of no greater than 2280°F based on an N1ST 714 reference standard and a liquidus temperature of no greater than 2155°F.
The present innovation provides a glass fiber composition comprising:
52 to 62 percent by weight Si02, 0 to 2 percent by weight Na20, 1'6 to 25 percent by weight CaO, 8 to 16 percent by weight AI203, 0.05 to 0.80 percent by weight Fe203; 0 to 2 percent by weight K20, 1.7 to 2.6 percent by weight MgO, 0 to 10 percent by weight B203, 0 to 2 percent by weight Ti02, 0 to..2 percent by weight BaO, 0 to 2 percent by weight Zr02; and 0 to 2 percent ;by weight SrO, and further including at least one material selected from the group consisting of: 0.05 to 1.5 percent by weight Li20, 0.05 to 1.5 percent by weight ZnO, 0.05 to 3 percent by weight MnO, and 0.05 to 3 percent by weight Mn02, wherein the glass composition has a forming temperature of no greater than 2280°F based on an N)ST 714 reference standard and a liquidus temperature of no greater than 2155°F. In one nonlimiting embodiment of the invention, the Si02 content is 57 to 59 percent by weight, the Na2~ content is up to 1 percent by weight, the Ca0 content is 22 to 24 percent by weight, the _5_ A1203 content is 12 to 14 percent by weight, the Fe203 content is up to 0.4 percent by weight, and the K20 content is up to 0.1 percent by weight, and the composition includes at least one material selected from the group consisting of: 0.2 to 1 percent by weight LizO, 0.2 to 1 percent by weight ZnO, up to 1 percent by weight MnO, and up to 1 percent by weight Mn02.
Brief Description of the Figure Figures 1 and 2 are graphs showing the relation between the amount of Mg0 and the liquidus temperature for glass fiber compositions of the present invention.
Detailed Description of the Invention The base composition for the glass fibers of the present invention suitable for textiles and glass fiber reinforcements includes the following main constituents in weight percent (wt%) based on the total weight of the final glass composition.
broad range preferred range most preferred range Si02 (wt%)52 to 62 55 to 61 57 to 59 Na20 (wt%)0 to 2 up to 1.5 up to 1 Ca0 (wt%) 16 to 25 20 to 25 22 to 24 AI203 (wt%)8 to 16 11 to 14 12 to 14 Fe203 (wt%)0.05 to 0.80up to 0.5 up to 0.4 K20 (wt%) 0 to 2 up to 1 up to 0.1 It should be appreciated that numerical values discussed herein, such as but not limited to weight percent of materials, length of time or temperatures, are approximate and are subject to variations due to various factors well known to those skilled in the art such as, but not limited to, measurement standards, equipment and techniques. For example, where it states in the present application that the range for Si02 is 52 to 62 weight percent, this range is about 52 to about 62 weight percent, and where it states that the forming temperature of a glass composition should be no greater than 2280°F ( 1249°C), the temperature is about 2280°F.
Mg0 is also a main constituent of the glass compositions of the present invention. It has been found that the heating and melting profile of a glass fiber composition, and in particular the liquidus temperature, can be controlled and in particular optimized by controlling the amount of MgO, which an object of the present invention and will be discussed later in more detail.
Oftentimes additional materials are added to the glass composition to modify the melt properties of the glass. For example, and without limiting the present invention, Li20, Zn02, Mn0 and Mn02 can be added to the glass fiber composition to reduce T~,Q. In one nonlimiting embodiment of the glass fibers of the present invention, the glass composition can include one or more of these materials in the following amounts.
broad range preferred range Li20 (wt%) 0.05 to 1.5 0.2 to 1 Zn0 (wt%) 0.05 to 1.5 0.2 to 1 Mn0 (wt%) 0.05 to 3 up to 1 Mn02 (wt%) 0.05 to 3 up to 1 It is believed that levels of these materials less than 0.05 wt% would be considered either tramp amounts or so low that they will not materially impact the glass melt properties.
Boron is another material that can be added to glass fiber compositions to reduce T~,Q. However, as discussed earlier, the inclusion of boron results in the production of particulates that, depending on the particulate level, may have to be removed from a melting furnace exhaust stream before being released into the environment. Although the amount of B203 in a glass fiber composition can be as high as 10 wt%, one nonlimiting embodiment of a glass composition of the present invention includes no greater than 3 wt% Bz03, preferably no greater than 2 wt% BZ03, and more preferably no greater than 1 wt% B203. fn another nonlimiting embodiment of the invention, the glass composition is essentially boron-free, i.e. it includes no more than a trace amount of B203, which is considered herein to be up to 0.05 wt% B203, and preferably does not include any B203.
It should be appreciated that glass fiber compositions can include other constituents and the present invention contemplates the inclusion of other materials in the glass fiber compositions, such as but not limited to, 0 to 2 wt% each of Ti02, BaO, Zr02 and SrO.
1n addition, because of the environmental concerns discussed earlier, although not limiting in the present invention, the glass compositions are preferably low fluorine compositions, i.e. no greater than 0.30 wt% fluorine, and more preferably are fluorine-free; i.e. it includes no more than a trace amount of fluorine, which is considered herein to be up to 0.05 wt% fluorine, and preferably does not include any fluorine.
It should be appreciated that the glass compositions disclosed herein can also include small amounts of other materials, for example melting and refining aids, tramp materials or impurities. For example and without limiting the present invention, melting and fining aids, such as S03, are useful during production of the glass, but their residual amounts in the glass can 20,. vary and have no material effect on the properties of the glass product.
In addition, small amounts of the additives discussed above can enter the glass composition as tramp materials or impurities included in the raw materials of the main constituents.
Commercial glass fibers of the present invention can be prepared in the conventional manner well known in the art, by blending the raw materials used to supply the specific oxides that form the composition ofithe fibers.
For example, typically sand is used for Si02, clay for AI203, lime or limestone for CaO, and dolomite for MgO and some of the CaO. As discussed earlier, the glass can include other additives that are added to modify the glass properties as well as small amounts of melting and refining aids, tramp materials or impurities.
After the ingredients are mixed in the proper proportions to provide the desired weight of each constituent for the: desired glass, the batch is melfed in a conventional glass fiber melting furnace and the resulting molten glass is passed along a conventional forehearth and into a glass fiber forming bushing located along the bottom of the forefiearth; as is weft known to those skilled in the art. During the glass melting phase, the glass is typically heated to a temperature of at least 2550°F (1400°C). The molten glass is then drawn or pulled through a plurality of holes in the bottom of the bushing. The streams of molten glass are attenuated to filaments by winding a strand of filaments on a. forming tube mounted on a rotatable collet of a winding machine.
Alternatively, the fiber forming apparatus can be, for example, a forming device for synthetic textile fibers or strands in which fibers are drawn from nozzles, such as but not limited to a spinneret, as is known to those skilled in the art. Typical forehearths and glass fiber forming arrangements are shown:
in K. Loewenstein, The Manufacturin4 Technology of Continuous Glass Fibres, (Third Edition 1993) at pages 85-107 and pages 115-135.
Tables 1-7 show laboratory examples of glass fiber compositions that illustrate the effect of Mg0 on the liquidus temperature of the glass compositions. Boron and fluorine were not included in these compositions.
The gtass fiber compositions shown in Tables 1-7 were prepared from reagent grade oxides (e.g.; pure silica or calcia). The batch size for each example was 1000 grams. The individual batch ingredients were weighed out, combined and placed in a tightly sealed jar. The sealed jar was then placed in a paint shaker for 15 minutes to effectively mix the ingredients. A
portion of the batch was then place into a platinum crucible, filling no more than 314 of its volume. The crucible was then placed in a furnace and heated _g_ to 2600°F (1425°C) for 15 minutes. The remaining batch was then added to the hot crucible and heated to 2600°F (1425°C) for 15 to 30 minutes. The furnace temperature was then raised to 2700°F (1482°C) and held there for 4 hours. The molten glass was then fritted in water and dried. The forming temperature, i.e. the glass temperature at a viscosity of 1000 poise, was determined by ASTM method C965-81, and the liquidus temperature by ASTM method C829-81.
The weight percent of the constituents of the compositions shown in Tables 1-7 are based on the weight percent of each constituent in the batch.
It is believed that the batch weight percent is generally about the same as the weight percent of the melted sample, except for glass batch materials that volatilize during melting, e.g. boron and fluorine. For boron, it is believed that the weight percent of B203 in a laboratory samples will be 5 to 10 percent less than the weight percent of B203 in the batch composition. For fluorine, it is believed that the weight percent of fluorine in a lab melt will be about 50 percent less than the weight percent of fluorine in the batch composition. It is further believed that glass fiber compositions made from commercial grade materials and melted under conventional operating conditions will have similar batch and melt weight percents as discussed above, except that the batch and melt weight percents for the volatile components of the composition will actually be closer to each other than the batch and melt wt% of the laboratory melts because in a conventional melting operation, the materials are exposed to the high melting temperatures for less time than the 4 hours of exposure for the laboratory melts.
Determination of the high temperature viscosity, TFORM, was based on the glass samples being compared against physical standards supplied by the National Institute of Standards and Testing (NIST). In Tables 1-7, TFoRnn is reported based on comparison to either NIST 717A, which is a borosilicate glass standard, or NIST 714, which is a soda lime glass standard. Although -10~
either standard can be used, it is believed that the NIST 714 reference standard is more reliable because it has been observed that the NIST
borosilicate standard 717A deteriorates at temperatures greater than 2150°F
(1177°C). In comparing TFORM based on the two different standards, generally TFORM based on NIST 714 is 20°F to 25°F (11°C to 16°C) higher than TFORM
based on NIST 717A. The T~,o is unaffected by the NIST standard.
Examples 1-7 in Table 1 show the change in the liquidus temperature of a typical glass fiber forming composition that further includes 1 wt% Ti02, as the amount of Mg0 is varied from 1.82 to 3 wt%. Examples 8-14 in Table 2 and Examples 15-30 in Table 3 show the change in the liquidus temperature of a typical glass fiber forming composition that further includes 1.5 or 1.1 wt% Ti02, respectively, and 0.90 wt% Li20, as the amount of Mg0 is varied from 1.7 to 3.5 wt%. Examples 31-38 in Table 4 show the change in the liquidus temperature of a typical glass fiber forming composition that further includes 0.5 wt% Ti02 and 0.90 wt% LizO, as the amount of Mg0 is varied from 1.7 to 3.12 wt%. Examples 39-49 in Table 5 show the change in the liquidus temperature of a typical glass fiber forming composition that further includes 1.1 wt% TiOz, 0.45 wt% Li20 and 0.45 wt% ZnO, as the amount of Mg0 is varied from 1.7 to 3.1 wt%. Examples 47-54 in Table 6 show the change in the liquidus temperature of a typical glass fiber forming composition that further includes 1.1 wt% Ti02 and 0.90 wt% ZnO, as the amount of Mg0 is varied from 1.7 to 3.1 wt%. Examples 59-66 in Table 7 show the change in the liquidus temperature of a typical glass fiber forming composition that further includes 1.1 wt% Ti02, 0.30 wt% Na20, 0.60 wt%
Li20 and 0.25 wt% Fe203 as the amount of Mg0 is varied from 1.7 to 3.1 wt%.
In addition, the forming temperatures for selected glass compositions are also included in Tables 1-7.
WO 00/73231 P~T/US00/14155 Tables 1-7 also include the ratio SiO2/RO, which is the ratio of the silica content of the batch, expressed as SiOZ, to the sum of the calcia and magnesia content, expressed as Ca0 and MgO, respectively.
Ex.1 Ex.2* Ex.3 Ex.4 Ex.S Ex.6 Ex.7 SiOz (wt%)59.83 59.61 60.13 60.43 60.43 59.61 59.61 AIz03 12.21 12.16 12.27 12.39 12.33 12.16 12.16 (wt%) Ca0 (wt%)22.80 23.51 22.92 23.14 23.03 24.31 24.31 Mg0 (wt%)3.00 2.62 2.50 2.00 2.00 1.82 1.82 Ti02 (wt%)1.00 1.00 1.00 1.00 1.00 1.00 1.00 Na20 (wt%)0.96 0.90 0.98 1.01 1.01 0.90 0.90 Fe203 0.20 0.20 0.20 0.20 0.20 0.20 0.20 (wt%) SiOz/RO 2.32 2.28 2.37 2.40 2.41 2.28 2.28 (F) TuQ(F) 2160 2138 2127 2149 2154 2161 2182 4T (F) 127 182 94 * average of five samples Ex.8 Ex.9 Ex.10 Ex.11 Ex.12 Ex.13 Ex.14 Si02 (wt%)59.62 59.30 59.97 60.09 60.21 60.33 60.75 AI203 (wt%)12.12 12.10 12.19 12.22 12.24 12.24 12.35 Ca0 (wt%) 22.12 22.60 22.25 22.30 22.34 22.39 22.55 Mg0 (wt%) 3.50 3.40 2.90 2.70 2.50 2.30 1.70 Ti02 (wt%)1.50 1.50 1.50 1.50 1.50 1.50 1.50 Li20 (wt%)0.90 0.90 0.90 0.90 0.90 0.90 0.90 Fe203 (wt%)0.25 0.20 0.25 0.25 0.25 0.25 0.25 Si02/RO 2.33 2.28 2.38 2.40 2.42 2.44 2.51 TFORM(F) 2196 2197 2192 2196 2223 2239 T~,Q (F) 2158 2136 2122 2152 2124 2120 2131 4T (F) 38 75 40 72 103 108 TFORM(F) 2219 2223 2215 2219 2248 2264 T~,Q (F) 2158 2136 2122 2152 2124 2120 2131 0T (F) 61 101 63 95 128 133 Ex.15 Ex.16 Ex.17 Ex.18 Ex.19 Ex.20 Ex.21 Ex.23 Si02 (wt%)59.61 59.61 59.73 59.85 59.97 60.09 60.10 60.10 AI203 (wt%)12.92 12.92 12.92 12.95 12.97 13.00 13.00 13.00 Ca0 (wt%) 21.91 21.96 22.00 22.04 22.09 22.13 22.15 22.15 Mg0 (wt%) 3.50 3.30 3.10 2.90 2.70 2.50 2.50 2.50 Ti02 (wt%)1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 Li20 (wt%)0.90 0.90 0.90 0.90 0.90 0.90 0.9 0.9 Fe203 (wt%)0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 SiOz/RO 2.35 2.36 2.38 2.40 2.42 2.44 2.44 2.44 TFORM ( F) T~,q (F) 2154 2138 2127 2122 2120 2111 4T (F) TFORM(F) 2215 2215 2217 2217 2226 2233 2255 2259 T~,o(F) 2154 2138 2127 2122 2120 2111 2070 2077 ~
4T (F) 61 77 90 95 106 122 185 182 TABLE 3 (cont.) Ex.23 Ex.24 Ex.25 Ex.26 Ex.27 Ex.28 Ex.29 Ex.30 Si02 (wt%)60.21 60.00 60.33 59.95 60.00 59.90 60.57 59.85 AI203 13.02 12.40 13.05 12.40 12.50 12.40 13.10 12.0 (wt%) Ca0 (wt%)22.18 22.05 22.22 23.30 23.70 23.55 22.31 23.80 Mg0 (wt%)2.30 2.30 2.10 2.10 1.90 1.90 1.70 1.70 TiOz (wt%)1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 LizO (wt%)0.90 0.90 0.90 0.90 0.90 0.90 0.90 0.90 Fez03 0.25 0.25 0.25 0.25 0.25 0.25 0.26 0.25 (wt%) Si02/RO 2.46 2.46 2.48 2.36 2.34 2.35 2.52 2.35 TFORM(F) 2226 2221 2273 2223 2237 2235 2210 T~,Q(F) 2088 2095 2077 2106 2082 2120 2086 2113 DT (F) 138 126 196 117 155 149 97 TFORM(F) 2251 2246 2296 2248 2262 2235 2262 2235 T~,Q(F) 2088 2095 2077 2106 2082 2113 2086 2113 4T(F) 163 151 219 142 180 122 176 122 Ex.31Ex.32 Ex.33Ex.34 Ex.35 Ex.36Ex.37 Ex.38 Si02 (wt%)60.0559.97 60.0960.21 60.23 60.2360.33 60.76 AI203 12.9812.19 12.2212.24 12.25 12.2512.27 12.35 (wt%) Ca0 (wt%)22.1423.56 23.3123.35 23.36 23.3623.40 23.56 Mg0 (wt%)3.12 2.90 2.70 2.50 2.50 2.50 2.30 1.70 Ti02 (wt%)0.55 0.50 0.50 0.50 0.51 0.51 0.50 0.50 Li20 (wt%)0.91 0.90 0.90 0.90 0.9 0.9 0.90 0.90 Fe203 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 (wt%) SiOz/RO 2.38 2.27 2.31 2.33 2.33 2.33 2.35 2.41 TFORM(F) 2264 2181 2197 2192 2196 2201 T~,Q(F) 2136 2138 2125 2124 2120 2116 2131 2149 ~T (F) 128 43 72 68 65 52 TFORM(F) 2205 2223 2215 2228 2235 2221 2226 T~,o(F) 2136 2138 2125 2124 2120 2116 2131 2149 OT (F) 68 98 91 108 119 90 77 Ex.39 Ex.40Ex.41Ex.42 Ex.43Ex.44 Ex.45Ex.46Ex.47 Ex.48Ex.49 SiO~ (wt%)59.73 59.8559.9760.09 60.2160.33 59.5460.4559.47 60.5759.40 AIz03 12.92 12.9512.9713.00 13.0213.05 12.1613.0812.16 13.1012.16 (wt%) Ca0 (wt%)22.00 22.0422.0922.13 22.18~ 22.2223.9522.2724.22 22.3124.49 Mg0 (wt%)3.10 2.90 2.70 2.50 2.30 2.10 2.10 1.90 1.90 1.70 1.70 Ti02 (wt%)1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 Li20 (wt%)0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45 Zn0 (wt%)0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45 I 0.450.45 ~
0.45 Fe~03 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 (wt%) ~ I ~ I I
i SiOz/RO 2.38 2.40 2.42 2.44 2.46 2.48 2.29 2.50 2.28 2.52 2.27 I I ~ ~ I
(F) T~,Q(F) 2142 2134 2109 2097 2091 2084 2111 2082 2118 2075 2134 OT(F) 100 114 141 162 166 189 130 191 203 114 I
, TFORM(F)2268 2275 2275 2284 2284 2300 2266 2300 2224 2305 2273 I
T~,o(F) 2142 2134 2109 2097 2091 2084 2111 2082 21 2075 2134 0T(F) 124 141 166 187 193 216 155 218 106 230 139 Ex.50 Ex.51 Ex.52 Ex.53 Ex.54 Ex.55 Ex.56 Ex.57 Ex.58 Si02 (wt%)59.73 59.85 59.97 58.80 60.09 60.21 60.33 60.45 60.57 AIz03 (wt%)12.92 12.95 12.97 13.33 13.00 13.02 13.05 13.08 13.10 Ca0 (wt%) 22.00 22.04 22.09 23.45 22.13 22.18 22.22 22.27 22.31 Mg0 (wt%) 3.10 2.90 2.70 2.50 2.50 2.30 2.10 1.90 1.70 Ti02 (wt%)1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 Zn0 (wt%) 0.90 0.90 0.90 0.9 0.90 0.90 0.90 0.90 0.90 Fe203 (wt%)0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 Si02/RO 2.38 2.40 2.42 2.27. 2.44 2.46 2.48 2.50 2.52 TFORM(F) 2282 2286 2296 2287 2304 2296 2307 2316 2298 TuQ(F) 2138 2131 2118 2129 2115 2131 2136 2128 2140 4T(F) 144 155 178 158 189 165 171 178 158 TFORM(F) 2309 2313 2323 2314 2332 2323 2336 2345 2327 TuQ(F) 2138 2131 2118 2129 2115 2131 2136 2138 2140 ~T(F) 171 182 205 185 217 192 200 207 187 _17_ Ex.59 Ex.60 I Ex.61Ex.62 Ex.63 Ex.64 Ex.65 Ex.66 Si02 (wt%)59.80 59.75 59.70 59.65 59.60 59.55 59.50 59.45 AI203 (wt%)12.25 12.25 12.25 12.25 12.25 12.25 12.25 12.25 Ca0 (wt%) 22.69 22.85 22.85 23.35 23.60 23.85 24.10 24.35 Mg0 (wt%) 3.10 2.90 2.70 2.50 2.30 2.10 1.90 1.70 Ti02 (wt%)1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 NazO (wt%)0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.30 Li20 (wt%)0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 Fe203 (wt%)0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 Si02/RO 2.33 2.32 2.34 2.31 2.30 2.29 2.29 2.28 TFORM(F) 2239 2242 2232 2235 2228 2228 2228 T~,(F) 2113 2113 2111 2118 2133 2143 2158 2178 4T (F) 126 131 113 103 85 70 50 TFORM(F) 2264 2257 2268 2257 2260 2253 2253 2253 T~,(F) 2113 2113 2111 2118 2133 2143 2158 2178 4T (F) 151 144 157 139 127 110 95 75 Figures 1 and 2 present curves illustrating the relationship between the forming temperature of the compositions shown in Tables 1-7 versus the amount of MgO, as discussed below in more detail. These curves are 2nd order polynomial curves generated using Microsoft~ Excel 97 SR-2(f).
Each of the curves shows that the amount of Mg0 impacts the liquidus temperature and in particular, there is a eutectic, i.e. minimum, in the liquidus temperature vs. the amount of MgO, indicating that the amount of Mg0 can be controlled to generate a minimum liquidus temperature for a glass fiber forming composition.
More specifically, Curve 1 in Figure 1 illustrates the relationship between the liquidus temperature and the amount of Mg0 in the glass compositions shown in Examples 1-7 in Table 1. In order to expand the Mg0 range to 3.5 weight percent, a control composition was also included in the curve. The control composition included 59.37 wt% Si02, 12.94 wt% AI203, 21.00 wt% CaO, 3.5 wt% MgO, 1.42 wt% Ti02, 1.01 wt% Na0 and 0.22 wt%
Fe203, and had a TL,Q of 2158°F. As can be seen, based on this curve, the liquidus temperature approaches a minimum in the range of 2.2 to 2.9 wt%
MgO, and reaches a minimum temperature at 2.45 to 2.65 wt% MgO.
Curve 2 in Figure 1 illustrates the relationship between the liquidus temperature and the amount of Mg0 in the glass compositions shown in Examples 8-14 in Table 2. As can be seen, based on this curve, the liquidus temperature approaches a minimum in the range of 1.85 to 2.6 wt% MgO, and reaches a minimum temperature at 2.0 to 2.45 wt% MgO.
Curve 3 in Figure 1 illustrates the relationship between the liquidus temperature and the amount of Mg0 in the glass compositions shown in Examples 15-30 in Table 3. As can be seen, based on this curve, the liquidus temperature approaches a minimum in the range of 1.8 to 2.5 wt% MgO, and reaches a minimum temperature at 2.0 to 2.3 wt% MgO.
Curve 4 in Figure 1 illustrates the relationship between the liquidus temperature and the amount of Mg0 in the glass compositions shown in Examples 31-38 in Table 4. As can be seen, based on this curve, the liquidus temperature approaches a minimum in the range of 2.3 to 2.7 wt% MgO, and reaches a minimum temperature at 2.35 to 2.6 wt% MgO.
Curve 5 in Figure 1 illustrates the relationship between the liquidus temperature and the amount of Mg0 in the glass compositions shown in Examples 39-49 in Table 5. As can be seen, based on this curve, the liquidus temperature approaches a minimum in the range of 1.8 to 2.5 wt% MgO, and reaches a minimum temperature at 2.0 to 2.3 wt% MgO.
Curve 6 in Figure 1 illustrates the relationship between the liquidus temperature and the amount of Mg0 in the glass compositions shown in Examples 50-58 in Table 6. As can be seen, based on this curve, the liquidus temperature approaches a minimum in the range of 2.3 to 2.7 wt% MgO, and reaches a minimum temperature at 2.4 to 2.6 wt% MgO.
_19_ Curve 7 in Figure 1 illustrates the relationship between the liquidus temperature and the amount of Mg0 in the glass compositions shown in Examples 59-66 in Table 7. The control sample discussed above was incorporated into Curve 7. As can be seen, based on this curve, the liquidus temperature approaches a minimum in the range of 2.7 to 3.2 wt% MgO, and reaches a minimum temperature at 2.8 to 3.1 wt% MgO.
As can be seen in Curves 1-7, the amount of Mg0 impacts the liquidus temperature and in particular, the amount of Mg0 can be controlled to generate a minimum liquidus temperature for a glass fiber forming composition.
Figure 2 Illustrates the relationship between the liquidus temperature and the amount of Mg0 for various combinations of Examples 8-58 in Tables 2-6. More specifically, Curve A plots the liquidus temperature versus the amount of Mg0 for the glass compositions shown in Tables 2, 3, and 4, Curve B plots the liquidus temperature versus the amount of Mg0 for the glass compositions shown in Tables 3, 5 and 6, and Curve C plots the liquidus temperature versus the amount of Mg0 for the Glass compositions shown in Tables 2-6. It is appreciated that Curves A, ~i and C combine the liquidus temperature for different glass compositions. More specifically, the glass compositions represented by Curve A have the same Li20 level but differ in the amount of Ti02, the glass compositions represented by Curve B
have the same amount of Ti02 but differ in the amount of LizO and Zn0 (although the total amount of Li20+Zn0 is the same), and the glass compositions represented by Curve C differ in the amounts of Ti02, Li20 and/or ZnO. However, these combinations are offered to illustrate the trend in the liquidus temperature as the amount of Mg0 varies.
Referring to Figure 2, it can be seen that the liquidus temperature for Curves A, B and C approaches a minimum in the range of 1.7 to 2.65 wt%
MgO, and reaches a minimum temperature at 1.90 to 2.55 wt% MgO.
The fact that the glass compositions of Tables 2-6 exhibit a minimum liquidus temperature (as shown in Curves 2-6, A, B and C) than the glass compositions of Table 1 (as shown in Curve 1 ) is to be expected since Examples 8-58 in Tables 2-6 all included additives, and in particular, LiZO
and/or ZnO, which reduce liquidus temperature. However, of particular significance is the fact that the minimum liquidus temperatures for the glass compositions of Tables 2-6 are generally within an Mg0 range lower than that of the glass compositions of Table 1.
In viewing Curves 1-7 and A-C in Figures 1 and 2, it is clear that the amount of Mg0 impacts the heating and melting profile of a glass fiber forming compositions, and in particular, the Mg0 content can be used to minimize the liquidus temperature of a glass fiber forming composition and allow for a lower forming temperature while maintaining the OT required to facilitate a continuous and uninterrupted glass fiber forming operation.
Examples 67-98 in Table 8 are additional examples of glass compositions of the present invention having 2.3 to 2.55 wt% Mg0 and a OT
of greater than 90°F based on a NIST 714 reference standard. These laboratory samples include up to 3 wt% B203, up to 0.9 wt% Na20, up to 1.1 wt% Ti02, up to 0.9 wt% Li20, up to 1 wt% ZnO, up to 3 wt% MnO, and up to 3 wt% Mn02 based on their batch composition, as discussed earlier. The samples were made in the same manner as those in Tables 1-7.
Ex.67 Ex.68**Ex.69 Ex.70 Ex.71 Ex.72 Ex.73 Ex.74 Si02 (wt%)60.12 59.61 59.11 58.61 60.12 59.01 59.31 59.61 AIz03 13.00 12.16 12.16 12.16 13.00 12.04 12.10 12.16 (wt%) Ca0 (wt%)21.13 23.50 23.00 23.50 21.13 23.27 23.38 23.50 Mg0 (wt%)2.50 2.50 2.50 2.50 2.50 2.48 2.49 2.50 Ti02 (wt%)1.10 1.10 1.10 1.10 1.10 1.09 1.09 1.10 8203 (wt%)1.00 0.30 1.00 1.00 1.00 1.00 0.50 0.50 Na20 (wt%) 0.89 0.89 Li20 (wt%) 0.20 0.90 0.90 0.90 0.50 Zn0 (wt%)0.90 0.20 Mn0 (wt%) 0.20 Mn02 (wt%) Fe203 0.25 0.23 0.23 0.23 0.25 0.23 0.23 0.23 (wt%) Si02/RO 2.54 2.29 2.32 2.25 2.54 2.29 2.29 2.29 TFORM(F) 2235 2247 2178 2172 2318 2260 2255 2221 T~,Q(F) 2082 2099 2088 2088 2172 2152 2154 2111 0T (F) 153 148 90 79 146 108 101 110 TFORM(F) 2260 2272 2201 2194 2345 2286 2280 2246 T~,Q(F) 2082 2099 2088 2088 2172 2152 2154 2111 4T (F) 178 173 113 106 173 134 126 135 ** average of two samples TABLE 8 (cont.) Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex.
75 76 77 78 79** 80** 81 82 **
Si02 (wt%)59.40 59.20 59.61 59.61 59.61 57.72 59.61 58.61 AI203 12.16 12.16 12.16 12.16 12.16 11.80 12.16 12.16 (wt%) Ca0 (wt%)23.49 23.69 23.50 23.50 20.50 22.80 20.50 23.50 Mg0 (wt%)2.30 2.30 2.50 2.50 2.50 2.52 2.50 2.50 Ti02 (wt%)1.10 1.10 1.10 1.10 1.10 1.07 1.10 1.10 BZO3 (wt%) 0.30 0.45 1.00 NazO (wt%)0.40 0.40 0.90 0.87 0.90 Li20 (wt%)0.45 0.45 0.30 0.30 Zn0 (wt%)0.45 0.45 0.30 0.45 0.30 Mn0 (wt%) 3.00 0.30 Mn02 (wt%) 3.00 3.00 Fe203 0.25 0.25 0.23 0.23 0.23 0.22 0.23 0.23 (wt%) Si02/RO 2.30 2.28 2.29 2.29 2.59 2.28 2.59 2.25 TFORM(F) 2246 2250 2235 2271 2221 2196 2224 2226 T~,Q(F) 2118 2105 2113 2113 2117 2125 2118 2082 4T (F) 128 145 122 158 104 71 106 144 TFORM(F) 2273 2277 2260 2298 2245 2219 2249 2251 T~,a(F) 2118 2105 2113 2113 2117 2125 2118 2082 4T (F) 155 172 147 185 128 94 131 169 ** average of two samples TABLE 8 (cont.) Ex.83 Ex.84 Ex.85 Ex.86 Ex.87 Ex.88 Ex.89 Ex.90 Si02 (wt%)58.96 58.70 58.35 57.65 58.15 57.95 58.20 58.10 AIz03 (wt%)13.24 13.35 13.20 13.40 13.20 13.20 13.03 13.03 Ca0 (wt%) 23.65 23.50 23.65 24.15 22.85 24.05 23.64 23.74 Mg0 (wt%) 2.5 2.50 2.55 2.55 2.55 2.55 2.50 2.50 Ti02 (wt%).50 0.50 1.10 1.10 1.10 1.10 0.50 0.50 B20g(Wt%) Na20 (wt%) 0.30 Li20 (wt%)0.90 0.90 0.90 0.90 0.90 0.90 0.90 0.90 Zn0 (wt%) 1.00 1.00 1.00 1.00 Mn0 (wt%) Mn02 (wt%) Fez03 (wt%)0.25 0.25 0.25 0.25 0.25 0.25 0.23 0.23 Si02/RO 2.25 2.26 2.23 2.16 2.29 2.18 2.23 2.21 TFORM ( F) Tua (F) 4T (F) TFORM(F) 2214 2212 2212 2203 2205 2183 2201 2203 T~,Q (F) 2116 2107 2095 2109 2077 .' 'a~E.~842098 2091 4T (F) 98 105 117 94 128 99 103 112 TABLE 8 (cont.) Ex.91 Ex.92 Ex.93 Ex.94 Ex.95 Ex.96 Ex.97 Ex.98 Si02 (wt%)58.00 58.10 58.30 57.60 56.25 55.75 56.00 57.75 AIz03 13.03 13.03 13.03 13.23 13.20 13.20 13.60 13.20 (wt%) Ca0 (wt%)23.84 23.74 23.54 23.84 23.75 23.25 24.25 24.25 Mg0 (wt%)2.50 2.50 2.50 2.50 2.50 2.55 2.50 2.55 Ti02 (wt%)0.50 0.50 0.50 0.50 1.10 1.10 0.50 1.10 8203 (wt%)1.00 1.00 1.00 1.20 2.00 3.00 2.00 NazO (wt%) 0.10 0.90 0.90 0.90 0.90 Li20 (wt%)0.90 0.90 0.90 0.80 Zn0 (wt%) Mn0 (wt%) Mn02 (wt%) Fe203 0.23 0.23 0.23 0.23 0.25 0.25 0.25 0.25 (wt%) SiOz/RO 2.20 2.21 2.24 2.19 2.14 2.16 2.09 2.15 TFORM
(F) TuQ (F) 4T (F) TFORM(F) 2178 2181 2183 2185 2235 2199 2215 2250 T~~Q(F) 2079 2075 2084 2071 2100 2060 2077 2131 DT (F) 99 106 99 114 135 139 138 119 Table 9 includes several glass fiber melt compositions made in a commercial glass melting operation. The amount of each constituent in the table is the weight percent in the actual melt. The weight percent for the LizO was determined using wet chemical analysis techniques, the weight percent for the B203 was determined using Neutron Transmission analysis techniques, and the weight percent for the remaining constituents was determined using X-ray fluorescence analysis (also referred to as "XRF analysis"), all of which are well know to those skilled in the art.
Ex.99 Ex.100 Ex.101Ex.102 Si02 (wt%)57.97 56.83 58.57 58.46 AI203 12.28 13.28 12.44 12.32 (wt%) Ca0 (wt%)24.15 23.71 23.85 23.70 Mg0 (wt%)2.6 2.45 2.42 2.48 Ti02 (wt%)1.16 0.55 0.51 0.50 8203 (wt%) 2.10 1.37 1.2 Na20 (wt%)0.89 0.87 Li20 (wt%) 0.84 0.88 K20 (wt%)0.06 0.06 0.07 0.07 ~
Fez03 0.28 0.28 0.27 0.275 (wt%) Si02/RO 2.17 2.17 2.23 2.23 (F) Tuo (F) 2140 2061 2082 2080 4T (F) 113 164 101 105 Based on the above, in one nonlimiting embodiment of the present invention, the glass fiber compositions have a base composition of Si02, CaO, A1203 and Fe203, and optionally NazO, as discussed above, and a Mg0 content ranging from 1.7 to 2.9 wt%, preferably from 1.8 to 2.9 wt%, and more preferably 1.8 to 2.7. In another nonlimiting embodiment, the glass fiber compositions have a Mg0 content ranging from 1.7 to 2.7 wt%, and preferably from 1.9 to 2.65 wt%.
In one nonlimiting embodiment of the invention, for glass compositions that do not include any liquidus temperature reducing additives other than Mg0 or only trace amounts of these additive, i.e. less than 0.05 wt, the Mg0 range is 2.2 to 2.9, preferably from 2.4 to 2.8 wt%, and more 2.45 to 2.65 wt%. In another embodiment of glass compositions with little or no liquidus temperature reducing additives other than MgO, the Mg0 range is from 2.2 to 2.7, and preferably from 2.3to2.6wt%.
_26_ In still another nonlimiting embodiment of the invention, in glass compositions that include a total amount of at least 0.05 wt% of liquidus temperature lowering additives, the Mg0 content ranges from 1.7 to 2.65 wt%, and preferably between 1.8 and 2.6 wt%, and more preferably 1.9 to 2.55 wt%. In another nonlimiting embodiment of glass compositions that include liquidus temperature lowering additives, the Mg0 content ranges from 1 .7 to 2.5 wt%, and preferably between 1.8 and 2.3 wt%. In one nonlimiting embodiment of the present invention, the liquidus temperature lowering additives in the glass fiber compositions include, but are not limited to, Li20, ZnO, MnO, Mn02 and/or B203 in the amounts discussed earlier.
It should be appreciated that although other commercially available glasses reduce environmental hazards due to boron and fluorine emissions by reducing or eliminating these materials from the batch, these glasses are processed at higher forming temperatures that conventional E-glass.
As a result, they require additional energy for production. The present invention provides glass compositions that include little or no boron and/or fluorine and have a forming temperature generally lower than other low boron and/or fluorine glass compositions, and boron-free and fluorine-free glass compositions, and more specifically, have forming temperatures approaching that of E-glass. In one nonlimiting embodiment of the invention, the forming temperature of the glass compositions of the present invention should be no greater than 2280°F ( 1249°C), and preferably no greater than 2260°F ( 1238°C), and more preferably no greater than 2230°F (1221°C), based on the NIST 714 reference standard. In one particular nonlimiting embodiment of the invention, the forming temperature is no greater than 2200°F ( 1204°C), based on the NIST 714 reference standard.
In addition, in one nonlimiting embodiment of the present invention, the liquidus temperature of the glass compositions of the present invention should be no greater than 2155°F ( 1 179°C), and preferably no greater than 2145°F ( 1 174°C), and more preferably no greater than 2130°F (1166°C).
As discussed earlierP in the glass fiber forming industry, 0T should be maintained in a range sufficient to prevent devitrification of the molten glass in the bushing area of a glass fiber forming operation and stagnant areas of the glass melting furnace. In the present invention, it 0T should be at least 65°F (36°C), preferably at least 90°F
(50°C), and more preferably at least 100°F (56°C). In addition, although not required, in order to maintain the overall heating and melting requirements of the glass fiber composition low, it is preferred that 4T be no greater than 1 50°F
(83°C) and more preferably no greater than 125°F (69°C).
This will maintain a lower forming temperature for a given liquidus temperature and result in good energy efficiency. If required, the amounts of Si02 and Ca0 can be modified to change the forming temperature ~ar~rl provide a desired 4T. More specifically, reducing the silica content while simultaneously maintaining or increasing the calcia content (thus reducing the Si02/RO
ratio) will reduce the forming temperature and thus reduce DT. This type of modification would be of value if, for example, ~T was much greater than 100°F and could be reduced without adversely affecting the glass melting and forming operation. Conversely, increasing the silica content and while simultaneously maintaining or reducing the calcia content (thus increasing the Si02/RO ratio) will raise the forming temperature and thus increase 4T. This type of modification would be of value if, for example, 0T was too low and had to be increased to at least 100°F. Compositional adjustments of the silica and/or calcia (and the resulting Si02/RO ratio) in _2g_ either direction are possible until the ~T is obtained that is deemed to facilitate the pursuit of a safe industrial melt forming process.
As discussed above, the Si02/RO ratio can be manipulated to further assist in achieving the goal of lowering the overall processing temperature, and in particular lowering the forming temperature while providing a OT required to facilitate continuous fiber forming operation.
Although not limiting in the present invention, the glass fiber compositions of the present invention have an Si02/RO ratio of no greater than 2.3, preferably no greater than 2.25, and more preferably no greater than 2.2.
The invention has been described with reference to specific embodiments, but it should be understood that variations and modifications that are known to those of skill in the art may be resorted to within the scope of the invention as defined by the claims.
typically greater than 100°F (56°C) and generally between 1'50°F (83°C} to 200°F (711 °C}. As used herein, the terms "forming temperature"
and "TFORM"
mean the temperature of the,glass at which the viscosity of the glass is log 3, or 1000 poise, and the terms "liquidus temperature" and "T~,Q" mean the temperature at which solid phase (crystals) and liquid phase (melt) are in equilibrium. The difference between TFORnn and TL,Q, referred to herein as "delta T" or "OT", is a common measure of the crystallization potential of a given melt composition. In the glass fiber forming industry, DT is typically maintained at a temperature of at least 90°F (50°C) in order to prevent devitrification of the molten glass in the bushing area of a glass fiber forming operation.
Boron and fluorine containing glass were developed to meet these operating conditions. More specifically, the boron and fluorine were included in the glass batch materials to act as fluxes during the glass melting operation: However; these materials are volatilized during melting and boron and fluorine emissions are released to the atmosphere. Since boron and fluorine are considered pollutants, these emissions are closely controlled by environmental regulations, which; in turn, requires careful control of the furnace operations and the use of expensive pollution control equipment. tn response to this, low boron and/or low fluorine E-glasses were developed. As used herein, "low boron" means that the glass composition is no greater than 5 weight percent boron, and preferably boron-free and "low fluorine"means that the glass composition is no greater than 1 weight percent fluorine, and preferably is fluorine-free.
For example, U.S. Patent No. 3,929,497 disctoses a boron-tree and fluorine-free glass composition containing titanium dioxide in the range of 0.5 to 5 percent by weight and Fe2G3 in the range of 5 to 15 percent by weight.
U.S: Patent No. 4,199,364 discloses a boron-free and fluorine-free glass composition that contains Li20 in the range of 0.1 to 1.5 percent by weight and may also include barium oxide. The liquidus temperature of the compositions is over 2200°F.
U.S. Patent No. 4,542,106 discloses a boron-free and fluorine-free glass composition that contains 1 to 5 percent by weight Ti02. The fibers also have a seed count of 5 seeds or less per cubic centimeter of glass and an electrical leakage value of 2.8 nanoamperes or less.
U.S. Patent No. 5,789,329 discloses a boron-free and fluorine-free glass composition that contains up to 0.9 percent by weight Ti02 and has a DT of at least 100°F (56°C).
For additional information concerning glass compositions and methods for fiberizing the glass composition, see K: Loewenstein, The Manufacturina Technolo4y of Continuous Glass Fibres, (3d Ed. 1993) at pages 30-44, 47-60, 115-122 and 126-135, and F. T. Walienberger (editor), Advanced inorganic Fibers: Processes. Structures, Properties. Replications, (2000) at pages 81-102 and 129-168.
Because the actual fiber forming operation is conducted at high temperatures, there are high energy costs associated with its production. in addition, the high temperatures accelerate the degradation of the refractory used in the glass melting furnace as well as the bushings used to form the fbers. The bushings include precious metals that cannot be recovered from the glass as the bushings corrode. It would be advantageous to produce the glass fibers at the lowest possible forming and liquidus temperatures so as to reduce the energy costs and thermal load on the furnace refractory and bushings, while at the same time provide the DT required to ensure an uninterrupted glass fiber forming, operation. Reducing the forming and liquidus temperatures of the glass compositions can also result in environmental benefits, such as but not limited to, a reduction in the amount of fuel required to generate the energy necessary for the fiber forming operation, as well as a reduction in the flue gas temperature. In addition,' it would be advantageous if the glass compositions are !ow fluoride andlor low boron compositions, and preferably are fluorine-free arydlor boron-free, so as to reduce or eliminate the environmental pollutants associated with these materials.
Summary of the invention The present innovation provides a glass fiber composition comprising:
52 to 62 percent by weight Si02, '0 to 2 percent by weight Na20, 16 to 25 percent by weight CaO, 8 to 16 percent by weight A1203, 0.05 to 0.80 percent by weight Fe203, 0 to 2 percent by weight K20, 1.7 to 2.9 percent by weight MgO; O to 10 percent by weight B203, 0 to 2 percent by weight Ti02, 0 to 2 percent by weight BaO, 0 to 2 percent by weight Zr02, and'0 to 2 percent by weight SrO, wherein the glass composition has a forming.temperature of no greater than 2280°F based on an NIST 714 reference standard and a liquidus temperature of no greater than 2155°F. In one noniirniting embodiment of the invention, the glass fiber composition . further includes at least one material selected from the group consisting of: 0.05 to 1.5 percent by weight Li20, '0.05 to 1.5 percent by weight ZnO, 0:05 to 3 percent by weight MnO, and 0.05 to 3 percent by weight Mn02.
The present invention also provides a glass fiber composition -consisting essentially of: 52 to 62 percent by weight Si02, 0 to 2 percent by weight Na20, 16 to 25 percent by weight CaO, 8 to 16 percent by weight 9 0 A1203, 0.05 to 0.80 percent by weight Fe203, O to 2 percent by weight KZO;
2.2 to 2.9 percent by weight MgO, 0 to 10 percent by weight 823, 0 to 2 percent by weight Ti02, 0 to 2 percent by weight BaO, 0 to 2 percent by weight Zr02, and O to 2 percent by weight SrO, wherein the glass composition has a forming temperature of no greater than 2280°F based on an N1ST 714 reference standard and a liquidus temperature of no greater than 2155°F.
The present innovation provides a glass fiber composition comprising:
52 to 62 percent by weight Si02, 0 to 2 percent by weight Na20, 1'6 to 25 percent by weight CaO, 8 to 16 percent by weight AI203, 0.05 to 0.80 percent by weight Fe203; 0 to 2 percent by weight K20, 1.7 to 2.6 percent by weight MgO, 0 to 10 percent by weight B203, 0 to 2 percent by weight Ti02, 0 to..2 percent by weight BaO, 0 to 2 percent by weight Zr02; and 0 to 2 percent ;by weight SrO, and further including at least one material selected from the group consisting of: 0.05 to 1.5 percent by weight Li20, 0.05 to 1.5 percent by weight ZnO, 0.05 to 3 percent by weight MnO, and 0.05 to 3 percent by weight Mn02, wherein the glass composition has a forming temperature of no greater than 2280°F based on an N)ST 714 reference standard and a liquidus temperature of no greater than 2155°F. In one nonlimiting embodiment of the invention, the Si02 content is 57 to 59 percent by weight, the Na2~ content is up to 1 percent by weight, the Ca0 content is 22 to 24 percent by weight, the _5_ A1203 content is 12 to 14 percent by weight, the Fe203 content is up to 0.4 percent by weight, and the K20 content is up to 0.1 percent by weight, and the composition includes at least one material selected from the group consisting of: 0.2 to 1 percent by weight LizO, 0.2 to 1 percent by weight ZnO, up to 1 percent by weight MnO, and up to 1 percent by weight Mn02.
Brief Description of the Figure Figures 1 and 2 are graphs showing the relation between the amount of Mg0 and the liquidus temperature for glass fiber compositions of the present invention.
Detailed Description of the Invention The base composition for the glass fibers of the present invention suitable for textiles and glass fiber reinforcements includes the following main constituents in weight percent (wt%) based on the total weight of the final glass composition.
broad range preferred range most preferred range Si02 (wt%)52 to 62 55 to 61 57 to 59 Na20 (wt%)0 to 2 up to 1.5 up to 1 Ca0 (wt%) 16 to 25 20 to 25 22 to 24 AI203 (wt%)8 to 16 11 to 14 12 to 14 Fe203 (wt%)0.05 to 0.80up to 0.5 up to 0.4 K20 (wt%) 0 to 2 up to 1 up to 0.1 It should be appreciated that numerical values discussed herein, such as but not limited to weight percent of materials, length of time or temperatures, are approximate and are subject to variations due to various factors well known to those skilled in the art such as, but not limited to, measurement standards, equipment and techniques. For example, where it states in the present application that the range for Si02 is 52 to 62 weight percent, this range is about 52 to about 62 weight percent, and where it states that the forming temperature of a glass composition should be no greater than 2280°F ( 1249°C), the temperature is about 2280°F.
Mg0 is also a main constituent of the glass compositions of the present invention. It has been found that the heating and melting profile of a glass fiber composition, and in particular the liquidus temperature, can be controlled and in particular optimized by controlling the amount of MgO, which an object of the present invention and will be discussed later in more detail.
Oftentimes additional materials are added to the glass composition to modify the melt properties of the glass. For example, and without limiting the present invention, Li20, Zn02, Mn0 and Mn02 can be added to the glass fiber composition to reduce T~,Q. In one nonlimiting embodiment of the glass fibers of the present invention, the glass composition can include one or more of these materials in the following amounts.
broad range preferred range Li20 (wt%) 0.05 to 1.5 0.2 to 1 Zn0 (wt%) 0.05 to 1.5 0.2 to 1 Mn0 (wt%) 0.05 to 3 up to 1 Mn02 (wt%) 0.05 to 3 up to 1 It is believed that levels of these materials less than 0.05 wt% would be considered either tramp amounts or so low that they will not materially impact the glass melt properties.
Boron is another material that can be added to glass fiber compositions to reduce T~,Q. However, as discussed earlier, the inclusion of boron results in the production of particulates that, depending on the particulate level, may have to be removed from a melting furnace exhaust stream before being released into the environment. Although the amount of B203 in a glass fiber composition can be as high as 10 wt%, one nonlimiting embodiment of a glass composition of the present invention includes no greater than 3 wt% Bz03, preferably no greater than 2 wt% BZ03, and more preferably no greater than 1 wt% B203. fn another nonlimiting embodiment of the invention, the glass composition is essentially boron-free, i.e. it includes no more than a trace amount of B203, which is considered herein to be up to 0.05 wt% B203, and preferably does not include any B203.
It should be appreciated that glass fiber compositions can include other constituents and the present invention contemplates the inclusion of other materials in the glass fiber compositions, such as but not limited to, 0 to 2 wt% each of Ti02, BaO, Zr02 and SrO.
1n addition, because of the environmental concerns discussed earlier, although not limiting in the present invention, the glass compositions are preferably low fluorine compositions, i.e. no greater than 0.30 wt% fluorine, and more preferably are fluorine-free; i.e. it includes no more than a trace amount of fluorine, which is considered herein to be up to 0.05 wt% fluorine, and preferably does not include any fluorine.
It should be appreciated that the glass compositions disclosed herein can also include small amounts of other materials, for example melting and refining aids, tramp materials or impurities. For example and without limiting the present invention, melting and fining aids, such as S03, are useful during production of the glass, but their residual amounts in the glass can 20,. vary and have no material effect on the properties of the glass product.
In addition, small amounts of the additives discussed above can enter the glass composition as tramp materials or impurities included in the raw materials of the main constituents.
Commercial glass fibers of the present invention can be prepared in the conventional manner well known in the art, by blending the raw materials used to supply the specific oxides that form the composition ofithe fibers.
For example, typically sand is used for Si02, clay for AI203, lime or limestone for CaO, and dolomite for MgO and some of the CaO. As discussed earlier, the glass can include other additives that are added to modify the glass properties as well as small amounts of melting and refining aids, tramp materials or impurities.
After the ingredients are mixed in the proper proportions to provide the desired weight of each constituent for the: desired glass, the batch is melfed in a conventional glass fiber melting furnace and the resulting molten glass is passed along a conventional forehearth and into a glass fiber forming bushing located along the bottom of the forefiearth; as is weft known to those skilled in the art. During the glass melting phase, the glass is typically heated to a temperature of at least 2550°F (1400°C). The molten glass is then drawn or pulled through a plurality of holes in the bottom of the bushing. The streams of molten glass are attenuated to filaments by winding a strand of filaments on a. forming tube mounted on a rotatable collet of a winding machine.
Alternatively, the fiber forming apparatus can be, for example, a forming device for synthetic textile fibers or strands in which fibers are drawn from nozzles, such as but not limited to a spinneret, as is known to those skilled in the art. Typical forehearths and glass fiber forming arrangements are shown:
in K. Loewenstein, The Manufacturin4 Technology of Continuous Glass Fibres, (Third Edition 1993) at pages 85-107 and pages 115-135.
Tables 1-7 show laboratory examples of glass fiber compositions that illustrate the effect of Mg0 on the liquidus temperature of the glass compositions. Boron and fluorine were not included in these compositions.
The gtass fiber compositions shown in Tables 1-7 were prepared from reagent grade oxides (e.g.; pure silica or calcia). The batch size for each example was 1000 grams. The individual batch ingredients were weighed out, combined and placed in a tightly sealed jar. The sealed jar was then placed in a paint shaker for 15 minutes to effectively mix the ingredients. A
portion of the batch was then place into a platinum crucible, filling no more than 314 of its volume. The crucible was then placed in a furnace and heated _g_ to 2600°F (1425°C) for 15 minutes. The remaining batch was then added to the hot crucible and heated to 2600°F (1425°C) for 15 to 30 minutes. The furnace temperature was then raised to 2700°F (1482°C) and held there for 4 hours. The molten glass was then fritted in water and dried. The forming temperature, i.e. the glass temperature at a viscosity of 1000 poise, was determined by ASTM method C965-81, and the liquidus temperature by ASTM method C829-81.
The weight percent of the constituents of the compositions shown in Tables 1-7 are based on the weight percent of each constituent in the batch.
It is believed that the batch weight percent is generally about the same as the weight percent of the melted sample, except for glass batch materials that volatilize during melting, e.g. boron and fluorine. For boron, it is believed that the weight percent of B203 in a laboratory samples will be 5 to 10 percent less than the weight percent of B203 in the batch composition. For fluorine, it is believed that the weight percent of fluorine in a lab melt will be about 50 percent less than the weight percent of fluorine in the batch composition. It is further believed that glass fiber compositions made from commercial grade materials and melted under conventional operating conditions will have similar batch and melt weight percents as discussed above, except that the batch and melt weight percents for the volatile components of the composition will actually be closer to each other than the batch and melt wt% of the laboratory melts because in a conventional melting operation, the materials are exposed to the high melting temperatures for less time than the 4 hours of exposure for the laboratory melts.
Determination of the high temperature viscosity, TFORM, was based on the glass samples being compared against physical standards supplied by the National Institute of Standards and Testing (NIST). In Tables 1-7, TFoRnn is reported based on comparison to either NIST 717A, which is a borosilicate glass standard, or NIST 714, which is a soda lime glass standard. Although -10~
either standard can be used, it is believed that the NIST 714 reference standard is more reliable because it has been observed that the NIST
borosilicate standard 717A deteriorates at temperatures greater than 2150°F
(1177°C). In comparing TFORM based on the two different standards, generally TFORM based on NIST 714 is 20°F to 25°F (11°C to 16°C) higher than TFORM
based on NIST 717A. The T~,o is unaffected by the NIST standard.
Examples 1-7 in Table 1 show the change in the liquidus temperature of a typical glass fiber forming composition that further includes 1 wt% Ti02, as the amount of Mg0 is varied from 1.82 to 3 wt%. Examples 8-14 in Table 2 and Examples 15-30 in Table 3 show the change in the liquidus temperature of a typical glass fiber forming composition that further includes 1.5 or 1.1 wt% Ti02, respectively, and 0.90 wt% Li20, as the amount of Mg0 is varied from 1.7 to 3.5 wt%. Examples 31-38 in Table 4 show the change in the liquidus temperature of a typical glass fiber forming composition that further includes 0.5 wt% Ti02 and 0.90 wt% LizO, as the amount of Mg0 is varied from 1.7 to 3.12 wt%. Examples 39-49 in Table 5 show the change in the liquidus temperature of a typical glass fiber forming composition that further includes 1.1 wt% TiOz, 0.45 wt% Li20 and 0.45 wt% ZnO, as the amount of Mg0 is varied from 1.7 to 3.1 wt%. Examples 47-54 in Table 6 show the change in the liquidus temperature of a typical glass fiber forming composition that further includes 1.1 wt% Ti02 and 0.90 wt% ZnO, as the amount of Mg0 is varied from 1.7 to 3.1 wt%. Examples 59-66 in Table 7 show the change in the liquidus temperature of a typical glass fiber forming composition that further includes 1.1 wt% Ti02, 0.30 wt% Na20, 0.60 wt%
Li20 and 0.25 wt% Fe203 as the amount of Mg0 is varied from 1.7 to 3.1 wt%.
In addition, the forming temperatures for selected glass compositions are also included in Tables 1-7.
WO 00/73231 P~T/US00/14155 Tables 1-7 also include the ratio SiO2/RO, which is the ratio of the silica content of the batch, expressed as SiOZ, to the sum of the calcia and magnesia content, expressed as Ca0 and MgO, respectively.
Ex.1 Ex.2* Ex.3 Ex.4 Ex.S Ex.6 Ex.7 SiOz (wt%)59.83 59.61 60.13 60.43 60.43 59.61 59.61 AIz03 12.21 12.16 12.27 12.39 12.33 12.16 12.16 (wt%) Ca0 (wt%)22.80 23.51 22.92 23.14 23.03 24.31 24.31 Mg0 (wt%)3.00 2.62 2.50 2.00 2.00 1.82 1.82 Ti02 (wt%)1.00 1.00 1.00 1.00 1.00 1.00 1.00 Na20 (wt%)0.96 0.90 0.98 1.01 1.01 0.90 0.90 Fe203 0.20 0.20 0.20 0.20 0.20 0.20 0.20 (wt%) SiOz/RO 2.32 2.28 2.37 2.40 2.41 2.28 2.28 (F) TuQ(F) 2160 2138 2127 2149 2154 2161 2182 4T (F) 127 182 94 * average of five samples Ex.8 Ex.9 Ex.10 Ex.11 Ex.12 Ex.13 Ex.14 Si02 (wt%)59.62 59.30 59.97 60.09 60.21 60.33 60.75 AI203 (wt%)12.12 12.10 12.19 12.22 12.24 12.24 12.35 Ca0 (wt%) 22.12 22.60 22.25 22.30 22.34 22.39 22.55 Mg0 (wt%) 3.50 3.40 2.90 2.70 2.50 2.30 1.70 Ti02 (wt%)1.50 1.50 1.50 1.50 1.50 1.50 1.50 Li20 (wt%)0.90 0.90 0.90 0.90 0.90 0.90 0.90 Fe203 (wt%)0.25 0.20 0.25 0.25 0.25 0.25 0.25 Si02/RO 2.33 2.28 2.38 2.40 2.42 2.44 2.51 TFORM(F) 2196 2197 2192 2196 2223 2239 T~,Q (F) 2158 2136 2122 2152 2124 2120 2131 4T (F) 38 75 40 72 103 108 TFORM(F) 2219 2223 2215 2219 2248 2264 T~,Q (F) 2158 2136 2122 2152 2124 2120 2131 0T (F) 61 101 63 95 128 133 Ex.15 Ex.16 Ex.17 Ex.18 Ex.19 Ex.20 Ex.21 Ex.23 Si02 (wt%)59.61 59.61 59.73 59.85 59.97 60.09 60.10 60.10 AI203 (wt%)12.92 12.92 12.92 12.95 12.97 13.00 13.00 13.00 Ca0 (wt%) 21.91 21.96 22.00 22.04 22.09 22.13 22.15 22.15 Mg0 (wt%) 3.50 3.30 3.10 2.90 2.70 2.50 2.50 2.50 Ti02 (wt%)1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 Li20 (wt%)0.90 0.90 0.90 0.90 0.90 0.90 0.9 0.9 Fe203 (wt%)0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 SiOz/RO 2.35 2.36 2.38 2.40 2.42 2.44 2.44 2.44 TFORM ( F) T~,q (F) 2154 2138 2127 2122 2120 2111 4T (F) TFORM(F) 2215 2215 2217 2217 2226 2233 2255 2259 T~,o(F) 2154 2138 2127 2122 2120 2111 2070 2077 ~
4T (F) 61 77 90 95 106 122 185 182 TABLE 3 (cont.) Ex.23 Ex.24 Ex.25 Ex.26 Ex.27 Ex.28 Ex.29 Ex.30 Si02 (wt%)60.21 60.00 60.33 59.95 60.00 59.90 60.57 59.85 AI203 13.02 12.40 13.05 12.40 12.50 12.40 13.10 12.0 (wt%) Ca0 (wt%)22.18 22.05 22.22 23.30 23.70 23.55 22.31 23.80 Mg0 (wt%)2.30 2.30 2.10 2.10 1.90 1.90 1.70 1.70 TiOz (wt%)1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 LizO (wt%)0.90 0.90 0.90 0.90 0.90 0.90 0.90 0.90 Fez03 0.25 0.25 0.25 0.25 0.25 0.25 0.26 0.25 (wt%) Si02/RO 2.46 2.46 2.48 2.36 2.34 2.35 2.52 2.35 TFORM(F) 2226 2221 2273 2223 2237 2235 2210 T~,Q(F) 2088 2095 2077 2106 2082 2120 2086 2113 DT (F) 138 126 196 117 155 149 97 TFORM(F) 2251 2246 2296 2248 2262 2235 2262 2235 T~,Q(F) 2088 2095 2077 2106 2082 2113 2086 2113 4T(F) 163 151 219 142 180 122 176 122 Ex.31Ex.32 Ex.33Ex.34 Ex.35 Ex.36Ex.37 Ex.38 Si02 (wt%)60.0559.97 60.0960.21 60.23 60.2360.33 60.76 AI203 12.9812.19 12.2212.24 12.25 12.2512.27 12.35 (wt%) Ca0 (wt%)22.1423.56 23.3123.35 23.36 23.3623.40 23.56 Mg0 (wt%)3.12 2.90 2.70 2.50 2.50 2.50 2.30 1.70 Ti02 (wt%)0.55 0.50 0.50 0.50 0.51 0.51 0.50 0.50 Li20 (wt%)0.91 0.90 0.90 0.90 0.9 0.9 0.90 0.90 Fe203 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 (wt%) SiOz/RO 2.38 2.27 2.31 2.33 2.33 2.33 2.35 2.41 TFORM(F) 2264 2181 2197 2192 2196 2201 T~,Q(F) 2136 2138 2125 2124 2120 2116 2131 2149 ~T (F) 128 43 72 68 65 52 TFORM(F) 2205 2223 2215 2228 2235 2221 2226 T~,o(F) 2136 2138 2125 2124 2120 2116 2131 2149 OT (F) 68 98 91 108 119 90 77 Ex.39 Ex.40Ex.41Ex.42 Ex.43Ex.44 Ex.45Ex.46Ex.47 Ex.48Ex.49 SiO~ (wt%)59.73 59.8559.9760.09 60.2160.33 59.5460.4559.47 60.5759.40 AIz03 12.92 12.9512.9713.00 13.0213.05 12.1613.0812.16 13.1012.16 (wt%) Ca0 (wt%)22.00 22.0422.0922.13 22.18~ 22.2223.9522.2724.22 22.3124.49 Mg0 (wt%)3.10 2.90 2.70 2.50 2.30 2.10 2.10 1.90 1.90 1.70 1.70 Ti02 (wt%)1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 Li20 (wt%)0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45 Zn0 (wt%)0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45 I 0.450.45 ~
0.45 Fe~03 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 (wt%) ~ I ~ I I
i SiOz/RO 2.38 2.40 2.42 2.44 2.46 2.48 2.29 2.50 2.28 2.52 2.27 I I ~ ~ I
(F) T~,Q(F) 2142 2134 2109 2097 2091 2084 2111 2082 2118 2075 2134 OT(F) 100 114 141 162 166 189 130 191 203 114 I
, TFORM(F)2268 2275 2275 2284 2284 2300 2266 2300 2224 2305 2273 I
T~,o(F) 2142 2134 2109 2097 2091 2084 2111 2082 21 2075 2134 0T(F) 124 141 166 187 193 216 155 218 106 230 139 Ex.50 Ex.51 Ex.52 Ex.53 Ex.54 Ex.55 Ex.56 Ex.57 Ex.58 Si02 (wt%)59.73 59.85 59.97 58.80 60.09 60.21 60.33 60.45 60.57 AIz03 (wt%)12.92 12.95 12.97 13.33 13.00 13.02 13.05 13.08 13.10 Ca0 (wt%) 22.00 22.04 22.09 23.45 22.13 22.18 22.22 22.27 22.31 Mg0 (wt%) 3.10 2.90 2.70 2.50 2.50 2.30 2.10 1.90 1.70 Ti02 (wt%)1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 Zn0 (wt%) 0.90 0.90 0.90 0.9 0.90 0.90 0.90 0.90 0.90 Fe203 (wt%)0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 Si02/RO 2.38 2.40 2.42 2.27. 2.44 2.46 2.48 2.50 2.52 TFORM(F) 2282 2286 2296 2287 2304 2296 2307 2316 2298 TuQ(F) 2138 2131 2118 2129 2115 2131 2136 2128 2140 4T(F) 144 155 178 158 189 165 171 178 158 TFORM(F) 2309 2313 2323 2314 2332 2323 2336 2345 2327 TuQ(F) 2138 2131 2118 2129 2115 2131 2136 2138 2140 ~T(F) 171 182 205 185 217 192 200 207 187 _17_ Ex.59 Ex.60 I Ex.61Ex.62 Ex.63 Ex.64 Ex.65 Ex.66 Si02 (wt%)59.80 59.75 59.70 59.65 59.60 59.55 59.50 59.45 AI203 (wt%)12.25 12.25 12.25 12.25 12.25 12.25 12.25 12.25 Ca0 (wt%) 22.69 22.85 22.85 23.35 23.60 23.85 24.10 24.35 Mg0 (wt%) 3.10 2.90 2.70 2.50 2.30 2.10 1.90 1.70 Ti02 (wt%)1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.10 NazO (wt%)0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.30 Li20 (wt%)0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 Fe203 (wt%)0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 Si02/RO 2.33 2.32 2.34 2.31 2.30 2.29 2.29 2.28 TFORM(F) 2239 2242 2232 2235 2228 2228 2228 T~,(F) 2113 2113 2111 2118 2133 2143 2158 2178 4T (F) 126 131 113 103 85 70 50 TFORM(F) 2264 2257 2268 2257 2260 2253 2253 2253 T~,(F) 2113 2113 2111 2118 2133 2143 2158 2178 4T (F) 151 144 157 139 127 110 95 75 Figures 1 and 2 present curves illustrating the relationship between the forming temperature of the compositions shown in Tables 1-7 versus the amount of MgO, as discussed below in more detail. These curves are 2nd order polynomial curves generated using Microsoft~ Excel 97 SR-2(f).
Each of the curves shows that the amount of Mg0 impacts the liquidus temperature and in particular, there is a eutectic, i.e. minimum, in the liquidus temperature vs. the amount of MgO, indicating that the amount of Mg0 can be controlled to generate a minimum liquidus temperature for a glass fiber forming composition.
More specifically, Curve 1 in Figure 1 illustrates the relationship between the liquidus temperature and the amount of Mg0 in the glass compositions shown in Examples 1-7 in Table 1. In order to expand the Mg0 range to 3.5 weight percent, a control composition was also included in the curve. The control composition included 59.37 wt% Si02, 12.94 wt% AI203, 21.00 wt% CaO, 3.5 wt% MgO, 1.42 wt% Ti02, 1.01 wt% Na0 and 0.22 wt%
Fe203, and had a TL,Q of 2158°F. As can be seen, based on this curve, the liquidus temperature approaches a minimum in the range of 2.2 to 2.9 wt%
MgO, and reaches a minimum temperature at 2.45 to 2.65 wt% MgO.
Curve 2 in Figure 1 illustrates the relationship between the liquidus temperature and the amount of Mg0 in the glass compositions shown in Examples 8-14 in Table 2. As can be seen, based on this curve, the liquidus temperature approaches a minimum in the range of 1.85 to 2.6 wt% MgO, and reaches a minimum temperature at 2.0 to 2.45 wt% MgO.
Curve 3 in Figure 1 illustrates the relationship between the liquidus temperature and the amount of Mg0 in the glass compositions shown in Examples 15-30 in Table 3. As can be seen, based on this curve, the liquidus temperature approaches a minimum in the range of 1.8 to 2.5 wt% MgO, and reaches a minimum temperature at 2.0 to 2.3 wt% MgO.
Curve 4 in Figure 1 illustrates the relationship between the liquidus temperature and the amount of Mg0 in the glass compositions shown in Examples 31-38 in Table 4. As can be seen, based on this curve, the liquidus temperature approaches a minimum in the range of 2.3 to 2.7 wt% MgO, and reaches a minimum temperature at 2.35 to 2.6 wt% MgO.
Curve 5 in Figure 1 illustrates the relationship between the liquidus temperature and the amount of Mg0 in the glass compositions shown in Examples 39-49 in Table 5. As can be seen, based on this curve, the liquidus temperature approaches a minimum in the range of 1.8 to 2.5 wt% MgO, and reaches a minimum temperature at 2.0 to 2.3 wt% MgO.
Curve 6 in Figure 1 illustrates the relationship between the liquidus temperature and the amount of Mg0 in the glass compositions shown in Examples 50-58 in Table 6. As can be seen, based on this curve, the liquidus temperature approaches a minimum in the range of 2.3 to 2.7 wt% MgO, and reaches a minimum temperature at 2.4 to 2.6 wt% MgO.
_19_ Curve 7 in Figure 1 illustrates the relationship between the liquidus temperature and the amount of Mg0 in the glass compositions shown in Examples 59-66 in Table 7. The control sample discussed above was incorporated into Curve 7. As can be seen, based on this curve, the liquidus temperature approaches a minimum in the range of 2.7 to 3.2 wt% MgO, and reaches a minimum temperature at 2.8 to 3.1 wt% MgO.
As can be seen in Curves 1-7, the amount of Mg0 impacts the liquidus temperature and in particular, the amount of Mg0 can be controlled to generate a minimum liquidus temperature for a glass fiber forming composition.
Figure 2 Illustrates the relationship between the liquidus temperature and the amount of Mg0 for various combinations of Examples 8-58 in Tables 2-6. More specifically, Curve A plots the liquidus temperature versus the amount of Mg0 for the glass compositions shown in Tables 2, 3, and 4, Curve B plots the liquidus temperature versus the amount of Mg0 for the glass compositions shown in Tables 3, 5 and 6, and Curve C plots the liquidus temperature versus the amount of Mg0 for the Glass compositions shown in Tables 2-6. It is appreciated that Curves A, ~i and C combine the liquidus temperature for different glass compositions. More specifically, the glass compositions represented by Curve A have the same Li20 level but differ in the amount of Ti02, the glass compositions represented by Curve B
have the same amount of Ti02 but differ in the amount of LizO and Zn0 (although the total amount of Li20+Zn0 is the same), and the glass compositions represented by Curve C differ in the amounts of Ti02, Li20 and/or ZnO. However, these combinations are offered to illustrate the trend in the liquidus temperature as the amount of Mg0 varies.
Referring to Figure 2, it can be seen that the liquidus temperature for Curves A, B and C approaches a minimum in the range of 1.7 to 2.65 wt%
MgO, and reaches a minimum temperature at 1.90 to 2.55 wt% MgO.
The fact that the glass compositions of Tables 2-6 exhibit a minimum liquidus temperature (as shown in Curves 2-6, A, B and C) than the glass compositions of Table 1 (as shown in Curve 1 ) is to be expected since Examples 8-58 in Tables 2-6 all included additives, and in particular, LiZO
and/or ZnO, which reduce liquidus temperature. However, of particular significance is the fact that the minimum liquidus temperatures for the glass compositions of Tables 2-6 are generally within an Mg0 range lower than that of the glass compositions of Table 1.
In viewing Curves 1-7 and A-C in Figures 1 and 2, it is clear that the amount of Mg0 impacts the heating and melting profile of a glass fiber forming compositions, and in particular, the Mg0 content can be used to minimize the liquidus temperature of a glass fiber forming composition and allow for a lower forming temperature while maintaining the OT required to facilitate a continuous and uninterrupted glass fiber forming operation.
Examples 67-98 in Table 8 are additional examples of glass compositions of the present invention having 2.3 to 2.55 wt% Mg0 and a OT
of greater than 90°F based on a NIST 714 reference standard. These laboratory samples include up to 3 wt% B203, up to 0.9 wt% Na20, up to 1.1 wt% Ti02, up to 0.9 wt% Li20, up to 1 wt% ZnO, up to 3 wt% MnO, and up to 3 wt% Mn02 based on their batch composition, as discussed earlier. The samples were made in the same manner as those in Tables 1-7.
Ex.67 Ex.68**Ex.69 Ex.70 Ex.71 Ex.72 Ex.73 Ex.74 Si02 (wt%)60.12 59.61 59.11 58.61 60.12 59.01 59.31 59.61 AIz03 13.00 12.16 12.16 12.16 13.00 12.04 12.10 12.16 (wt%) Ca0 (wt%)21.13 23.50 23.00 23.50 21.13 23.27 23.38 23.50 Mg0 (wt%)2.50 2.50 2.50 2.50 2.50 2.48 2.49 2.50 Ti02 (wt%)1.10 1.10 1.10 1.10 1.10 1.09 1.09 1.10 8203 (wt%)1.00 0.30 1.00 1.00 1.00 1.00 0.50 0.50 Na20 (wt%) 0.89 0.89 Li20 (wt%) 0.20 0.90 0.90 0.90 0.50 Zn0 (wt%)0.90 0.20 Mn0 (wt%) 0.20 Mn02 (wt%) Fe203 0.25 0.23 0.23 0.23 0.25 0.23 0.23 0.23 (wt%) Si02/RO 2.54 2.29 2.32 2.25 2.54 2.29 2.29 2.29 TFORM(F) 2235 2247 2178 2172 2318 2260 2255 2221 T~,Q(F) 2082 2099 2088 2088 2172 2152 2154 2111 0T (F) 153 148 90 79 146 108 101 110 TFORM(F) 2260 2272 2201 2194 2345 2286 2280 2246 T~,Q(F) 2082 2099 2088 2088 2172 2152 2154 2111 4T (F) 178 173 113 106 173 134 126 135 ** average of two samples TABLE 8 (cont.) Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex.
75 76 77 78 79** 80** 81 82 **
Si02 (wt%)59.40 59.20 59.61 59.61 59.61 57.72 59.61 58.61 AI203 12.16 12.16 12.16 12.16 12.16 11.80 12.16 12.16 (wt%) Ca0 (wt%)23.49 23.69 23.50 23.50 20.50 22.80 20.50 23.50 Mg0 (wt%)2.30 2.30 2.50 2.50 2.50 2.52 2.50 2.50 Ti02 (wt%)1.10 1.10 1.10 1.10 1.10 1.07 1.10 1.10 BZO3 (wt%) 0.30 0.45 1.00 NazO (wt%)0.40 0.40 0.90 0.87 0.90 Li20 (wt%)0.45 0.45 0.30 0.30 Zn0 (wt%)0.45 0.45 0.30 0.45 0.30 Mn0 (wt%) 3.00 0.30 Mn02 (wt%) 3.00 3.00 Fe203 0.25 0.25 0.23 0.23 0.23 0.22 0.23 0.23 (wt%) Si02/RO 2.30 2.28 2.29 2.29 2.59 2.28 2.59 2.25 TFORM(F) 2246 2250 2235 2271 2221 2196 2224 2226 T~,Q(F) 2118 2105 2113 2113 2117 2125 2118 2082 4T (F) 128 145 122 158 104 71 106 144 TFORM(F) 2273 2277 2260 2298 2245 2219 2249 2251 T~,a(F) 2118 2105 2113 2113 2117 2125 2118 2082 4T (F) 155 172 147 185 128 94 131 169 ** average of two samples TABLE 8 (cont.) Ex.83 Ex.84 Ex.85 Ex.86 Ex.87 Ex.88 Ex.89 Ex.90 Si02 (wt%)58.96 58.70 58.35 57.65 58.15 57.95 58.20 58.10 AIz03 (wt%)13.24 13.35 13.20 13.40 13.20 13.20 13.03 13.03 Ca0 (wt%) 23.65 23.50 23.65 24.15 22.85 24.05 23.64 23.74 Mg0 (wt%) 2.5 2.50 2.55 2.55 2.55 2.55 2.50 2.50 Ti02 (wt%).50 0.50 1.10 1.10 1.10 1.10 0.50 0.50 B20g(Wt%) Na20 (wt%) 0.30 Li20 (wt%)0.90 0.90 0.90 0.90 0.90 0.90 0.90 0.90 Zn0 (wt%) 1.00 1.00 1.00 1.00 Mn0 (wt%) Mn02 (wt%) Fez03 (wt%)0.25 0.25 0.25 0.25 0.25 0.25 0.23 0.23 Si02/RO 2.25 2.26 2.23 2.16 2.29 2.18 2.23 2.21 TFORM ( F) Tua (F) 4T (F) TFORM(F) 2214 2212 2212 2203 2205 2183 2201 2203 T~,Q (F) 2116 2107 2095 2109 2077 .' 'a~E.~842098 2091 4T (F) 98 105 117 94 128 99 103 112 TABLE 8 (cont.) Ex.91 Ex.92 Ex.93 Ex.94 Ex.95 Ex.96 Ex.97 Ex.98 Si02 (wt%)58.00 58.10 58.30 57.60 56.25 55.75 56.00 57.75 AIz03 13.03 13.03 13.03 13.23 13.20 13.20 13.60 13.20 (wt%) Ca0 (wt%)23.84 23.74 23.54 23.84 23.75 23.25 24.25 24.25 Mg0 (wt%)2.50 2.50 2.50 2.50 2.50 2.55 2.50 2.55 Ti02 (wt%)0.50 0.50 0.50 0.50 1.10 1.10 0.50 1.10 8203 (wt%)1.00 1.00 1.00 1.20 2.00 3.00 2.00 NazO (wt%) 0.10 0.90 0.90 0.90 0.90 Li20 (wt%)0.90 0.90 0.90 0.80 Zn0 (wt%) Mn0 (wt%) Mn02 (wt%) Fe203 0.23 0.23 0.23 0.23 0.25 0.25 0.25 0.25 (wt%) SiOz/RO 2.20 2.21 2.24 2.19 2.14 2.16 2.09 2.15 TFORM
(F) TuQ (F) 4T (F) TFORM(F) 2178 2181 2183 2185 2235 2199 2215 2250 T~~Q(F) 2079 2075 2084 2071 2100 2060 2077 2131 DT (F) 99 106 99 114 135 139 138 119 Table 9 includes several glass fiber melt compositions made in a commercial glass melting operation. The amount of each constituent in the table is the weight percent in the actual melt. The weight percent for the LizO was determined using wet chemical analysis techniques, the weight percent for the B203 was determined using Neutron Transmission analysis techniques, and the weight percent for the remaining constituents was determined using X-ray fluorescence analysis (also referred to as "XRF analysis"), all of which are well know to those skilled in the art.
Ex.99 Ex.100 Ex.101Ex.102 Si02 (wt%)57.97 56.83 58.57 58.46 AI203 12.28 13.28 12.44 12.32 (wt%) Ca0 (wt%)24.15 23.71 23.85 23.70 Mg0 (wt%)2.6 2.45 2.42 2.48 Ti02 (wt%)1.16 0.55 0.51 0.50 8203 (wt%) 2.10 1.37 1.2 Na20 (wt%)0.89 0.87 Li20 (wt%) 0.84 0.88 K20 (wt%)0.06 0.06 0.07 0.07 ~
Fez03 0.28 0.28 0.27 0.275 (wt%) Si02/RO 2.17 2.17 2.23 2.23 (F) Tuo (F) 2140 2061 2082 2080 4T (F) 113 164 101 105 Based on the above, in one nonlimiting embodiment of the present invention, the glass fiber compositions have a base composition of Si02, CaO, A1203 and Fe203, and optionally NazO, as discussed above, and a Mg0 content ranging from 1.7 to 2.9 wt%, preferably from 1.8 to 2.9 wt%, and more preferably 1.8 to 2.7. In another nonlimiting embodiment, the glass fiber compositions have a Mg0 content ranging from 1.7 to 2.7 wt%, and preferably from 1.9 to 2.65 wt%.
In one nonlimiting embodiment of the invention, for glass compositions that do not include any liquidus temperature reducing additives other than Mg0 or only trace amounts of these additive, i.e. less than 0.05 wt, the Mg0 range is 2.2 to 2.9, preferably from 2.4 to 2.8 wt%, and more 2.45 to 2.65 wt%. In another embodiment of glass compositions with little or no liquidus temperature reducing additives other than MgO, the Mg0 range is from 2.2 to 2.7, and preferably from 2.3to2.6wt%.
_26_ In still another nonlimiting embodiment of the invention, in glass compositions that include a total amount of at least 0.05 wt% of liquidus temperature lowering additives, the Mg0 content ranges from 1.7 to 2.65 wt%, and preferably between 1.8 and 2.6 wt%, and more preferably 1.9 to 2.55 wt%. In another nonlimiting embodiment of glass compositions that include liquidus temperature lowering additives, the Mg0 content ranges from 1 .7 to 2.5 wt%, and preferably between 1.8 and 2.3 wt%. In one nonlimiting embodiment of the present invention, the liquidus temperature lowering additives in the glass fiber compositions include, but are not limited to, Li20, ZnO, MnO, Mn02 and/or B203 in the amounts discussed earlier.
It should be appreciated that although other commercially available glasses reduce environmental hazards due to boron and fluorine emissions by reducing or eliminating these materials from the batch, these glasses are processed at higher forming temperatures that conventional E-glass.
As a result, they require additional energy for production. The present invention provides glass compositions that include little or no boron and/or fluorine and have a forming temperature generally lower than other low boron and/or fluorine glass compositions, and boron-free and fluorine-free glass compositions, and more specifically, have forming temperatures approaching that of E-glass. In one nonlimiting embodiment of the invention, the forming temperature of the glass compositions of the present invention should be no greater than 2280°F ( 1249°C), and preferably no greater than 2260°F ( 1238°C), and more preferably no greater than 2230°F (1221°C), based on the NIST 714 reference standard. In one particular nonlimiting embodiment of the invention, the forming temperature is no greater than 2200°F ( 1204°C), based on the NIST 714 reference standard.
In addition, in one nonlimiting embodiment of the present invention, the liquidus temperature of the glass compositions of the present invention should be no greater than 2155°F ( 1 179°C), and preferably no greater than 2145°F ( 1 174°C), and more preferably no greater than 2130°F (1166°C).
As discussed earlierP in the glass fiber forming industry, 0T should be maintained in a range sufficient to prevent devitrification of the molten glass in the bushing area of a glass fiber forming operation and stagnant areas of the glass melting furnace. In the present invention, it 0T should be at least 65°F (36°C), preferably at least 90°F
(50°C), and more preferably at least 100°F (56°C). In addition, although not required, in order to maintain the overall heating and melting requirements of the glass fiber composition low, it is preferred that 4T be no greater than 1 50°F
(83°C) and more preferably no greater than 125°F (69°C).
This will maintain a lower forming temperature for a given liquidus temperature and result in good energy efficiency. If required, the amounts of Si02 and Ca0 can be modified to change the forming temperature ~ar~rl provide a desired 4T. More specifically, reducing the silica content while simultaneously maintaining or increasing the calcia content (thus reducing the Si02/RO
ratio) will reduce the forming temperature and thus reduce DT. This type of modification would be of value if, for example, ~T was much greater than 100°F and could be reduced without adversely affecting the glass melting and forming operation. Conversely, increasing the silica content and while simultaneously maintaining or reducing the calcia content (thus increasing the Si02/RO ratio) will raise the forming temperature and thus increase 4T. This type of modification would be of value if, for example, 0T was too low and had to be increased to at least 100°F. Compositional adjustments of the silica and/or calcia (and the resulting Si02/RO ratio) in _2g_ either direction are possible until the ~T is obtained that is deemed to facilitate the pursuit of a safe industrial melt forming process.
As discussed above, the Si02/RO ratio can be manipulated to further assist in achieving the goal of lowering the overall processing temperature, and in particular lowering the forming temperature while providing a OT required to facilitate continuous fiber forming operation.
Although not limiting in the present invention, the glass fiber compositions of the present invention have an Si02/RO ratio of no greater than 2.3, preferably no greater than 2.25, and more preferably no greater than 2.2.
The invention has been described with reference to specific embodiments, but it should be understood that variations and modifications that are known to those of skill in the art may be resorted to within the scope of the invention as defined by the claims.
Claims (22)
1. ~A glass fiber composition comprising:
SiO2 52 to 59 percent by weight;
Na2O 0 to 2 percent by weight; ~
CaO~ 16 to 25 percent by weight;
Al2O3 8 to 16 percent by weight;
Fe2O3 0.05 to 0.80 percent by weight;
K2O3 ~ 0 to 2 percent by weight;
MgO~ 1.7 to 2.9 percent by weight;
B2O3 0.05 to 2 percent by weight;
TiO2 0 to 2 percent by weight; and Li2O 0.2 to 1 percent by weight;
wherein the glass composition has a weight ratio of SiO2 to RO no greater than 2.3, wherein RO is the sum of the CaO and MgO content.
SiO2 52 to 59 percent by weight;
Na2O 0 to 2 percent by weight; ~
CaO~ 16 to 25 percent by weight;
Al2O3 8 to 16 percent by weight;
Fe2O3 0.05 to 0.80 percent by weight;
K2O3 ~ 0 to 2 percent by weight;
MgO~ 1.7 to 2.9 percent by weight;
B2O3 0.05 to 2 percent by weight;
TiO2 0 to 2 percent by weight; and Li2O 0.2 to 1 percent by weight;
wherein the glass composition has a weight ratio of SiO2 to RO no greater than 2.3, wherein RO is the sum of the CaO and MgO content.
2. ~The glass fiber composition according to claim 1, wherein the glass composition has a forming temperature of no greater than 2200°F based on an NIST 714 reference standard and a liquidus temperature of no greater than 2100°F.
3. ~The glass fiber composition according to claim 1, wherein the glass composition has a forming temperature of no greater than 2190°F based on an NIST 714 reference standard and a liquidus temperature of no greater than 2090°F.
4. ~The glass fiber composition according to claim 1, wherein the MgO content is 2.2 to 2.9 percent by weight.
5. ~The glass fiber composition according to claim 1, wherein the MgO content is 2.4 to 2.7 percent by weight.
6. ~The glass fiber composition according to claim 1, wherein the glass composition has a B2O3 content of 0.5 to 1.5 percent by weight.
7. ~The glass fiber composition according to claim 1, wherein the SiO2 content is 52 to 59 percent by weight, the CaO content is 20 to 25 percent by weight, the Al2O3 content is 11 to 14 percent by weight, and the TiO2 content is 0.5 to 2 percent by weight.
8. ~The glass fiber composition according to claim 1, wherein the SiO2 content is 57 to 59 percent by weight, the CaO content is 22 to 24 percent by weight, the Al2O3 content is 12 to 14 percent by weight, and the TiO2 content is 0.5 to 1.5 percent by weight.
9. ~A glass fiber composition consisting essentially of:
SiO2 ~52 to 59 percent by weight;~
Na2O ~0 to 2 percent by weight;
CaO ~16 to 25 percent by weight;
Al2O3 ~8 to 16 percent by weight;
Fe2O3 ~0.05 to 0.80 percent by weight;
K2O ~0 to 2 percent by weight;
MgO ~1.7 to 2.9 percent by weight;
B2O3 ~0.05 to 2 percent by weight;
TiO2 ~0 to 2 percent by weight; and Li20 ~0.2 to 1 percent by weight;
wherein the glass composition has a weight ratio of SiO2 to RO no greater than 2.3, wherein RO is the sum of the CaO and MgO content.
SiO2 ~52 to 59 percent by weight;~
Na2O ~0 to 2 percent by weight;
CaO ~16 to 25 percent by weight;
Al2O3 ~8 to 16 percent by weight;
Fe2O3 ~0.05 to 0.80 percent by weight;
K2O ~0 to 2 percent by weight;
MgO ~1.7 to 2.9 percent by weight;
B2O3 ~0.05 to 2 percent by weight;
TiO2 ~0 to 2 percent by weight; and Li20 ~0.2 to 1 percent by weight;
wherein the glass composition has a weight ratio of SiO2 to RO no greater than 2.3, wherein RO is the sum of the CaO and MgO content.
10. ~The glass fiber composition according to claim 9, wherein the glass composition has a forming temperature of no greater than 2200°F based on an NIST 714 reference standard and a liquidus temperature of no greater than 2100°F.
11. ~The glass fiber composition according to claim 9, wherein the glass composition has a forming temperature of no greater than 2190°F based on an NIST 714 reference standard and a liquidus temperature of no greater than 2090°F.
12. ~The glass fiber composition according to claim 9, wherein the MgO content is 2.2 to 2.9 percent by weight.
13. ~The glass fiber composition according to claim 9, wherein the MgO content is 2.4 to 2.7 percent by weight.
14. ~The glass fiber composition according to claim 9, wherein the glass composition has a B2O3 content of 0.5 to 1.5 percent by weight.
15. ~The glass fiber composition according to claim 9, wherein the SiO2 content is 52 to 59 percent by weight, the CaO content is 20 to 25 percent by weight, the Al2O3 content is 11 to 14 percent by weight, and the TiO2 content is 0.5 to 2 percent by weight.
16. ~The glass fiber composition according to claim 9, wherein the SiO2 content is 57 to 59 percent by weight, the CaO content is 22 to 24 percent by weight, the Al2O3 content is 12 to 14 percent by weight, and the TiO2 content is 0.5 to 1.5 percent by weight.
17. ~The glass fiber composition according to claim 9, wherein the composition has a .DELTA.T of at least 65°F.
18. ~A glass fiber composition comprising:
SiO2 ~57 to 59 percent by weight;
Na2o 0 to 2 percent by weight;
CaO 22 to 24 percent by weight;
Al2O3 12 to 14 percent by weight;
Fe2O3 0.05 to 0.80 percent by weight;
K2O 0 to 2 percent by weight;
MgO 2.4 to 2.7 percent by weight;
B2O3 0.5 to 1.5 percent by weight;
TiO2 0.5 to 1.5 percent by weight; and Li2O 0.2 to 1 percent by weight;
wherein the glass composition has a weight ratio of SiO2 to RO no greater than 2.3, wherein RO is the sum of the CaO and MgO content.
SiO2 ~57 to 59 percent by weight;
Na2o 0 to 2 percent by weight;
CaO 22 to 24 percent by weight;
Al2O3 12 to 14 percent by weight;
Fe2O3 0.05 to 0.80 percent by weight;
K2O 0 to 2 percent by weight;
MgO 2.4 to 2.7 percent by weight;
B2O3 0.5 to 1.5 percent by weight;
TiO2 0.5 to 1.5 percent by weight; and Li2O 0.2 to 1 percent by weight;
wherein the glass composition has a weight ratio of SiO2 to RO no greater than 2.3, wherein RO is the sum of the CaO and MgO content.
19. ~The glass fiber composition according to claim 18, wherein the glass composition has a forming temperature of no greater than 2200°F based on an NIST 714 reference standard and a liquidus temperature of no greater than 2100°F.
20. ~The glass fiber composition according to claim 18, wherein the glass composition has a forming temperature of no greater than 2190°F based on an NIST 714 reference standard and a liquidus temperature of no greater than 2090°F.
21. ~The glass fiber composition according to claim 19, wherein the composition has a .DELTA. of at least 65°F.
22. ~The glass fiber composition according to claim 19, wherein the composition has a .DELTA.T of at least 90°F.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US13653899P | 1999-05-28 | 1999-05-28 | |
| US60/136,538 | 1999-05-28 | ||
| PCT/US2000/014155 WO2000073231A1 (en) | 1999-05-28 | 2000-05-23 | Glass fiber composition |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2375719A1 CA2375719A1 (en) | 2000-12-07 |
| CA2375719C true CA2375719C (en) | 2007-01-09 |
Family
ID=22473273
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002375719A Expired - Fee Related CA2375719C (en) | 1999-05-28 | 2000-05-23 | Glass fiber composition |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP1189846A1 (en) |
| JP (1) | JP2003500330A (en) |
| CA (1) | CA2375719C (en) |
| WO (1) | WO2000073231A1 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6962886B2 (en) * | 1999-05-28 | 2005-11-08 | Ppg Industries Ohio, Inc. | Glass Fiber forming compositions |
| BR0107212B1 (en) | 2000-09-06 | 2011-07-12 | Fiberglass composition. | |
| JP4874520B2 (en) | 2001-10-18 | 2012-02-15 | ピーピージー インダストリーズ オハイオ，インコーポレイテッド | Glass fiber forming composition |
| US7022634B2 (en) * | 2003-07-07 | 2006-04-04 | Johns Manville | Low boron E-glass composition |
| US7449419B2 (en) * | 2003-09-09 | 2008-11-11 | Ppg Industries Ohio, Inc. | Glass compositions, glass fibers, and methods of inhibiting boron volatization from glass compositions |
| FR2867776B1 (en) * | 2004-03-17 | 2006-06-23 | Saint Gobain Vetrotex | GLASS YARNS FOR REINFORCING ORGANIC AND / OR INORGANIC MATERIALS |
| FR2867775B1 (en) | 2004-03-17 | 2006-05-26 | Saint Gobain Vetrotex | GLASS YARNS FOR REINFORCING ORGANIC AND / OR INORGANIC MATERIALS |
| KR100843011B1 (en) | 2004-12-24 | 2008-07-01 | 니혼 이타가라스 가부시키가이샤 | Scaly glass |
| JP5442181B2 (en) | 2005-07-05 | 2014-03-12 | 日本電気硝子株式会社 | Glass fiber composition, glass fiber and glass fiber-containing composite material |
| EP2042474B1 (en) * | 2006-06-23 | 2013-03-20 | Nippon Sheet Glass Company, Limited | Glass flake |
| FR2910462B1 (en) * | 2006-12-22 | 2010-04-23 | Saint Gobain Vetrotex | GLASS YARNS FOR REINFORCING ORGANIC AND / OR INORGANIC MATERIALS |
| WO2009145254A1 (en) * | 2008-05-28 | 2009-12-03 | 日本板硝子株式会社 | Scale‑like glass and covered scale‑like glass |
| DE102008037955B3 (en) * | 2008-08-14 | 2010-04-15 | Bürger, Gerhard | High temperature and chemically resistant glass with improved UV light transmission and its use |
| CN103244793B (en) * | 2013-05-31 | 2015-12-09 | 重庆再升科技股份有限公司 | A kind of novel glass fiber core material of vacuum heat insulation plate and preparation method |
| CN112320883B (en) * | 2021-01-07 | 2021-03-19 | 格润化学(东营)有限公司 | Sewage treatment agent and preparation method thereof |
| TW202402701A (en) * | 2022-03-30 | 2024-01-16 | 日商日本板硝子股份有限公司 | Glass fibers |
| WO2023190983A1 (en) * | 2022-03-30 | 2023-10-05 | 日本板硝子株式会社 | Glass fiber |
| TW202402702A (en) * | 2022-03-30 | 2024-01-16 | 日商日本板硝子股份有限公司 | Glass fiber |
| CN115368011B (en) * | 2022-09-09 | 2023-06-23 | 中国建筑材料科学研究总院有限公司 | Core-skin glass with good compatibility matching for optical fiber image transmission element and preparation method thereof |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| IL42018A (en) * | 1972-04-28 | 1977-10-31 | Owens Corning Fiberglass Corp | Fiberizable boron and fluorine free glass compositions |
| US4066466A (en) * | 1976-07-22 | 1978-01-03 | Ppg Industries, Inc. | Low pollution glass fiber compositions |
| US4542106A (en) * | 1983-12-19 | 1985-09-17 | Ppg Industries, Inc. | Fiber glass composition |
| JPS63225552A (en) * | 1987-03-13 | 1988-09-20 | Nitto Boseki Co Ltd | Glass composition absorbing ultraviolet ray for fiber |
| FR2692248B1 (en) * | 1992-06-16 | 1995-08-04 | Vetrotex France Sa | ACID RESISTANT GLASS FIBERS. |
| RU2027687C1 (en) * | 1992-12-28 | 1995-01-27 | Александр Иванович Фокин | Glass for fiber glass |
| AU692712B2 (en) * | 1995-06-06 | 1998-06-11 | Owens Corning | Boron-free glass fibers |
| FR2768144B1 (en) * | 1997-09-10 | 1999-10-01 | Vetrotex France Sa | GLASS YARNS SUITABLE FOR REINFORCING ORGANIC AND / OR INORGANIC MATERIALS |
-
2000
- 2000-05-23 EP EP00936210A patent/EP1189846A1/en not_active Withdrawn
- 2000-05-23 WO PCT/US2000/014155 patent/WO2000073231A1/en active Application Filing
- 2000-05-23 JP JP2000621302A patent/JP2003500330A/en active Pending
- 2000-05-23 CA CA002375719A patent/CA2375719C/en not_active Expired - Fee Related
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| JP2003500330A (en) | 2003-01-07 |
| WO2000073231A1 (en) | 2000-12-07 |
| EP1189846A1 (en) | 2002-03-27 |
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