Electronic-grade low-dielectric-loss glass fiber composition and composite material

Abstract

The electronic-grade low-dielectric glass fiber composition provided by the invention comprises the following components in percentage by mass: 54-60% of SiO2; 12% to 18% of Al2O3; 5 to 14.9% of CaO; 0.2% to 3.0% of MgO; 5.6% to 14.5% of B2O3; 0 to 2.0% of F; 0% to 0.4% of Na2O + K2O; 0 to 0.5 percent of Fe2O3 (ferric oxide); 0.1 to 3% of TiO2; from 0 to 3.5% of Y2O3; 0% to 3.5% of La2O3; and 0 to 3.0% of CeO2. The dielectric constant of the glass fiber is smaller than or equal to 5.5, the dielectric loss is smaller than or equal to 0.004 (under the frequency of 10GHz), the forming temperature does not exceed 1300 DEG C, the forming interval is larger than 50 DEG C, and the glass fiber can be produced in batches on a ten-thousand-ton tank furnace.

Description

Technical Field

[0001] This invention relates to the field of glass fiber technology, and in particular to an electronic-grade low-dielectric glass fiber composition and composite material. Background Technology

[0002] With the rapid development of the electronics and information industry, printed circuit boards (PCBs) are evolving towards higher density, multilayering, and higher frequency, which places higher demands on the dielectric properties of PCBs. The PCB substrate is mainly composed of glass fiber and epoxy resin, with glass fiber having the highest volume proportion and the greatest impact on the overall dielectric properties of the circuit board. Currently, most PCBs use E-glass, which has advantages such as good processability, good water resistance, and low price. However, its dielectric constant (Dk) is relatively high (approximately 6.7), and its dielectric loss (Df) is relatively large, typically greater than 60 × 10⁻⁶ at 10 GHz frequencies. -4 It is becoming increasingly difficult to meet the demands of high density and high-speed information processing.

[0003] To reduce the dielectric properties of glass fibers, low-dielectric glass fibers, such as D-glass and L-glass (AGY), have been developed. Although these low-dielectric glass fibers have significantly reduced dielectric constant and dielectric loss, they all use a high B2O3 (mass content exceeding 20%) and low R2O (mass content less than 0.1%) formulation, resulting in high glass melting temperature, poor compositional uniformity, easy generation of veins and bubbles, and difficulties in fiber drawing. Both the productivity and workability are poor, making it difficult to achieve large-scale mass production and meet the rapidly expanding market demand.

[0004] Chinese patent CN202111323970.1 discloses a low dielectric loss glass fiber composition comprising the following components: SiO2: 50-60%; B2O3: 20-30%; Al2O3: 8-18%; CaO: 1-6%; F: 0.2-1.50%; SnO2: 0.05-0.5%; Li2O: 0.05-0.5%; K2O+Na2O≤0.05%. To achieve low dielectric constant and dielectric loss, this invention not only contains a high content of B2O3 but also adds SnO2 and Li2O. While exhibiting excellent performance, it is difficult and costly to produce, hindering large-scale mass production.

[0005] Therefore, developing a new type of electronic-grade low-dielectric-loss glass fiber with low dielectric constant, low dielectric loss, good manufacturability, and mass production capability has become an urgent problem to be solved in the electronics industry. Summary of the Invention

[0006] In view of this, the technical problem to be solved by the present invention is to provide a glass fiber composition, which has the characteristics of low dielectric constant and low dielectric loss.

[0007] This invention provides an electronic-grade low-dielectric glass fiber composition comprising the following components by weight percentage:

[0008] 54%~60% SiO2;

[0009] 12%~18% Al2O3;

[0010] 5-14.9% CaO;

[0011] 0.2%~3.0% MgO;

[0012] 5.6%~14.5% B2O3;

[0013] 0~2.0% F;

[0014] 0~0.4% Na₂O + K₂O;

[0015] 0~0.5% Fe2O3;

[0016] 0.1%~3% TiO2;

[0017] 0~3.5% Y2O3;

[0018] 0~3.5% La2O3;

[0019] 0~3.0% CeO2.

[0020] The dielectric properties of glass are mainly related to the atomic polarization within the glass. When electrons or ions in the glass are subjected to an external electric field, they undergo displacement polarization or orientation polarization. The higher the degree of polarization, the greater the dielectric constant of the glass. Simultaneously, due to polarization, some electrical energy is converted into heat energy and lost; the higher the polarization, the greater the dielectric loss. Therefore, increasing the density of the glass network structure, reducing the content of mobile ions, and adding network ions with stronger electric fields all help to reduce the degree of glass polarization, thereby reducing the dielectric constant and dielectric loss. Existing low-dielectric glass fibers typically achieve lower dielectric constants and dielectric losses by significantly increasing the B2O3 content (above 20%) and reducing the alkaline earth metal oxide (RO) content (CaO+MgO less than 10%). However, excessively high B2O3 content not only significantly increases the glass fiber melting temperature and production difficulty (forming temperature above 1330℃, only small-batch production via crucible method or electric melting furnace), but also makes it difficult to solve the problem of large fluctuations in glass composition and the easy generation of secondary bubbles caused by the easy volatilization of B2O3 at high temperatures (the ultrafine electronic cloth used in printed circuit boards is very sensitive to the glass bubble content and composition fluctuations, and the requirements are very stringent). Therefore, the current market production of low-dielectric glass fibers is very limited, and the price is also very high.

[0021] The glass fiber of this invention is based on the SiO2-Al2O3-RO ternary glass system. By balancing and controlling the content of the three key components, SiO2, B2O3 and CaO, the fiber forming process of the glass fiber is significantly optimized while ensuring that the dielectric properties of the glass meet the application standards. This enables the large-scale preparation of ultrafine electronic-grade glass yarn in large-scale tank furnace production equipment.

[0022] Meanwhile, this invention further enhances the stability of the glass network structure and effectively suppresses atomic polarization by introducing specific doses of highly coordinated, high-field-strength metal oxides (including TiO2, CeO2, Y2O3, and La2O3) into the glass fiber composition. Tests show that the dielectric constant and dielectric loss of the glass fiber prepared by this invention are reduced by more than 30% compared to traditional E-type glass.

[0023] Furthermore, our research revealed that ions in alkali metal oxides such as K₂O and Na₂O exhibit strong polarization sensitivity, which can significantly negatively impact the dielectric properties of glass. Therefore, in the formulation system of this invention, the total content and relative proportion of K₂O and Na₂O are strictly limited, and components such as BaO, ZnO, and PbO are largely avoided in the glass composition.

[0024] This invention successfully prepared an electronic-grade glass fiber with ultra-low dielectric properties through directional design of the glass composition and precise control of the content and ratio of each component: under 10GHz testing conditions, its dielectric constant (Dk) ≤ 5.5 and dielectric loss (Df) ≤ 40 × 10⁻ 4 Meanwhile, the glass composition exhibits excellent adaptability to fiber forming processes—forming temperature ≤1300℃, crystallization upper limit temperature ≤1200℃, and can directly utilize existing large-scale tank furnace production lines to achieve large-scale production of ultrafine electronic yarns.

[0025] In the glass composition system of the present invention, silicon dioxide (SiO2) is the core oxide for constructing the glass network framework. Its main functions include: optimizing the glass drawing process performance, reducing the dielectric constant and dielectric loss, and at the same time giving the glass matrix the necessary mechanical strength and chemical stability.

[0026] It should be noted that there is a significant balance between SiO2 content and glass performance: within a reasonable range, increasing the SiO2 content can simultaneously enhance the mechanical strength of the glass and reduce its dielectric parameters; however, with an excessive increase in SiO2 content, the melting temperature and fiber forming temperature of the glass will increase significantly, leading to a substantial increase in the difficulty of the production process.

[0027] In this invention, the mass percentage of SiO2 is limited to 54%-60%, preferably 55.2%-60%, and more preferably 56.5%-59.5%.

[0028] The electronic-grade low-dielectric glass fiber composition provided by the present invention comprises 54% to 60 wt% SiO2; specifically, it can be 54 wt%, 55 wt%, 56 wt%, 57 wt%, 58 wt%, 59 wt%, or 60 wt%.

[0029] In the glass network system of this invention, Al2O3 (alumina) is also a key oxide component supporting the network framework. When the Al2O3 content is within a reasonable range, it will form aluminum-oxygen tetrahedra ([AlO4]). 5 The coordination form of ⁻) is embedded in the glass network structure. This process can effectively enhance the spatial stability of the network and has a positive effect on reducing the dielectric constant and dielectric loss of the glass fiber.

[0030] The Al2O3 mass percentage of the composition of the present invention is limited to 12% to 18%, preferably 13% to 17%, and more preferably 13.2% to 16.4%.

[0031] The electronic-grade low-dielectric glass fiber composition provided by the present invention comprises 12-18 wt% Al2O3; specifically, it can be 12wt%, 13wt%, 14wt%, 15wt%, 16wt%, 17wt%, or 18wt%.

[0032] CaO (calcium oxide), as a typical alkaline earth metal oxide, plays a key role in fluxing and regulating in silicate glass systems: it can effectively reduce the high-temperature viscosity of glass melt, optimize the material properties of glass fibers (such as flowability and formability during drawing), and inhibit the crystallization tendency of glass, which is crucial for the continuous and stable production of ultrafine glass fibers.

[0033] It is important to note that the CaO content must be strictly controlled and balanced: because the radius of Ca²⁺ ions is relatively large, they are prone to ion displacement polarization in an electromagnetic field environment. If the CaO content is too high, it will significantly enhance the polarization response of the glass, thereby negatively affecting key electrical performance indicators such as dielectric constant and dielectric loss.

[0034] In this invention, the CaO content is controlled at 5%-14.9%, preferably 5.8%-14.2% by mass, and more preferably 6.2%-12.8%.

[0035] The electronic-grade low-dielectric glass fiber composition provided by the present invention comprises 5% to 14.9 wt% CaO; specifically, it can be 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, 11 wt%, 12 wt%, 13 wt%, or 14 wt%.

[0036] Similar to CaO, MgO belongs to the alkaline earth metal oxides, but MgO has a greater influence on the tendency of glass crystallization. Typically, the mass percentage of MgO in electronic yarn does not exceed 3%. In this invention, the MgO content is controlled at 0.2-3%, preferably 0.2%-2.8%, and more preferably 0.5-2.5%.

[0037] The electronic-grade low-dielectric glass fiber composition provided by this invention comprises 0.2~3.0 wt% MgO; specifically, it can be 0.2wt%, 0.3wt%, 0.4wt%, 0.5wt%, 0.6wt%, 0.7wt%, 0.8wt%, 0.9wt%, 1.0wt%, 1.1wt%, 1.2wt%, 1.3wt%, 1.4wt%, 1.5wt%, 1.6wt%, 1.7wt%, 1.8wt%, 1.9wt%, 2.0wt%, 2.1wt%, 2.2wt%, 2.3wt%, 2.4wt%, 2.5wt%, 2.6wt%, 2.7wt%, 2.8wt%, 2.9wt%, or 3.0wt%.

[0038] The glass fiber composition of this invention incorporates a B2O3 (boron oxide) component. In an alkali-free glass system, when the amount of B2O3 added is low, it integrates into the glass network structure in a boron-oxygen tetrahedral ([BO4]⁻) coordination mode. This process effectively reduces the high-temperature viscosity of the glass melt and plays a positive role in optimizing the dielectric properties of the glass. Simultaneously, by precisely controlling the B2O3 content, the surface tension characteristics of the glass fiber during the drawing process can be flexibly adjusted. This technique provides crucial support for the continuous and stable forming of ultrafine glass fibers.

[0039] The glass fiber of the present invention contains 5.6% to 14.5% B2O3 by mass, preferably 7.5% to 14.3%, and more preferably 9.5% to 13.5%.

[0040] The electronic-grade low-dielectric glass fiber composition provided by this invention comprises 5.6%~14.5wt% B2O3; specifically, it can be:

[0041] 5.6wt%, 5.7wt%, 5.8wt%, 5.9wt%, 6.0wt%, 6.1wt%, 6.2wt%, 6.3wt%, 6.4wt%, 6.5wt%, 6.6wt%, 6.7wt%, 6.8wt%, 6.9wt%, 7.0wt%, 7.1wt%, 7.2wt%, 7.3wt%, 7.4wt%, 7.5wt%, 7.6wt%, 7.7wt%, 7.8wt%, 7.9wt%, 8 .0wt%, 8.1wt%, 8.2wt%, 8.3wt%, 8.4wt%, 8.5wt%, 8.6wt%, 8.7wt%, 8.8wt%, 8.9wt%, 9.0wt%, 9.1wt%, 9 .2wt%, 9.3wt%, 9.4wt%, 9.5wt%, 9.6wt%, 9.7wt%, 9.8wt%, 9.9wt%, 10.0wt%, 10.1wt%, 10.2wt%, 10.3wt %, 10.4wt%, 10.5wt%, 10.6wt%, 10.7wt%, 10.8wt%, 10.9wt%, 11.0wt%, 11.1wt%, 11.2wt%, 11.3wt%, 11 .4wt%, 11.5wt%, 11.6wt%, 11.7wt%, 11.8wt%, 11.9wt%, 12.0wt%, 12.1wt%, 12.2wt%, 12.3wt%, 12.4wt% , 12.5wt%, 12.6wt%, 12.7wt%, 12.8wt%, 12.9wt%, 13.0wt%, 13.1wt%, 13.2wt%, 13.3wt%, 13.4wt%, 13. 5wt%, 13.6wt%, 13.7wt%, 13.8wt%, 13.9wt%, 14.0wt%, 14.1wt%, 14.2wt%, 14.3wt%, 14.4wt%, 14.5wt%.

[0042] According to the present invention, the CaO+MgO content is 16%~22wt%, specifically 16wt%, 17wt%, 18wt%, 19wt%, 20wt%, 21wt%, and 22wt%.

[0043] The content of CeO2+Y2O3+La2O3 is 0~3.8 wt%, specifically 0.0wt%, 0.1wt%, 0.2wt%, 0.3wt%, 0.4wt%, 0.5wt%, 0.6wt%, 0.7wt%, 0.8wt%, 0.9wt%, 1.0wt%, 1.1wt%, 1.2wt%, 1.3wt%, 1.4wt%, 1.5wt%, 1.6wt%, 1.7wt%, 1.8wt%, 1.9wt%, 2.0wt%, 2.1wt%, 2.2wt%, 2.3wt%, 2.4wt%, 2.5wt%, 2.6wt%, 2.7wt%, 2.8wt%, 2.9wt%, 3.0wt%, 3.1wt%, 3.2wt%, 3.3wt%, 3.4wt%, 3.5wt%, 3.6wt%, 3.7wt%, and 3.8wt%.

[0044] The ratio of TiO2 + Y2O3 + La2O3 is 0.5%~4 wt%. Specifically, it can be 0.5wt%, 0.7wt%, 0.9wt%, 1.1wt%, 1.3wt%, 1.5wt%, 1.7wt%, 1.9wt%, 2.1wt%, 2.3wt%, 2.5wt%, 2.7wt%, 2.9wt%, 3.1wt%, 3.3wt%, 3.5wt%, 3.7wt%, and 3.9wt%.

[0045] As a preferred embodiment, the CaO+MgO content is 18%~20.3%, the CeO2+Y2O3+La2O3 content is 1.1~3.5%, and the TiO2+Y2O3+La2O3 ratio is 1.5~3.5%.

[0046] Na2O (sodium oxide) and K2O (potassium oxide) both belong to the category of alkali metal oxides and can play a dual role in glass systems: on the one hand, they act as fluxes to lower the melting temperature of glass, thereby simplifying the fiber drawing process; on the other hand, the introduction of alkali metal ions can significantly increase the polarization of glass, which has a negative impact on electrical performance indicators such as dielectric constant and dielectric loss.

[0047] Based on the above performance balance, the present invention strictly limits the content of alkali metal oxides in the glass composition: the total mass ratio of Na2O and K2O needs to be controlled within the range of 0-0.4%, with the preferred range being 0-0.3% and the more preferred range being 0-0.2%.

[0048] TiO2 (titanium dioxide), La2O3 (lanthanum oxide), Y2O3 (yttrium oxide), and CeO2 (cerium oxide) are all high-coordination, high-field-strength oxides. Their core mechanism of action includes: by enhancing the aggregation degree of the glass network (i.e., the compactness of the network structure), suppressing the displacement polarization effect of ions, and thus simultaneously reducing the electrical conductivity loss, structural loss, and relaxation loss of the glass. This characteristic makes the introduction of the above oxides effective in optimizing the dielectric properties of the glass.

[0049] Through experiments, the invention team further discovered that if one of the above oxides is added alone and in excessive amounts, the crystallization driving force of the glass will be significantly enhanced, leading to crystallization defects in the fiber forming process. However, by introducing multiple components synergistically and precisely controlling their respective contents, the complementary effect between different oxides can be utilized to optimize dielectric properties while effectively suppressing the crystallization tendency of the glass, ultimately achieving the best balance between performance and process.

[0050] In this invention, the content of TiO2 is limited to 0.1-3%, the content of Y2O3 to 0-3.5%, the content of La2O3 to 0-3.5%, the content of CeO2 to 0-3%, the combined value of TiO2, La2O3, and Y2O3 to 0-3.8%, and the combined value of CeO2, La2O3, and Y2O3 to 0-3.8%. Preferably, the content of TiO2 is 0.1-2.4%, the content of Y2O3 is 0.5-3%, the content of La2O3 is 0.3-3%, the content of CeO2 is 0.2-2%, the combined value of TiO2, La2O3, and Y2O3 is 1.5-3.5%, and the combined value of CeO2, La2O3, and Y2O3 is 1.1-3.5%. More preferably, the TiO2 content is 0.1-2.4%, the Y2O3 content is 0.5-2.5%, the La2O3 content is 0.3-2%, the CeO2 content is 0.2-1.8%, the combined value of TiO2, La2O3 and Y2O3 is 1.5-3.2%, and the combined value of CeO2, La2O3 and Y2O3 is 1.4-3.3%.

[0051] Fe2O3 is generally not added to glass fibers, as a high content can cause the glass to turn yellow or green. In this invention, Fe2O3 exists only as a mineral raw material impurity, and its content is controlled at 0-0.6%, more preferably 0-0.4%.

[0052] In a preferred embodiment of the present invention, the electronic-grade low-dielectric glass fiber composition comprises:

[0053] The composition consists of 55.2%~60% SiO2; 13%~17% Al2O3; 5.8%~14.2% CaO; 0.5%~2.8% MgO; 7.5%~14.3% B2O3; 0~1.2% F; 0~0.5% Fe2O3; 0~0.4% Na2O + K2O; 0.1%~2.4% TiO2; 0.2%~2.0% CeO2; 0.5%~3.0% Y2O3; and 0.3%~3.0% La2O3. The CaO + MgO content is 9%~15.1%, the CeO2 + Y2O3 + La2O3 content is 1.1%~3.5%, and the TiO2 + Y2O3 + La2O3 ratio is 1.5%~3.5%.

[0054] In a preferred embodiment of the present invention, the electronic-grade low-dielectric glass fiber composition comprises:

[0055] The composition consists of 56.5%~59.5% SiO2; 13.2%~16.4% Al2O3; 6.2%~12.8% CaO; 0.5%~2.5% MgO; 9.5%~13.5% B2O3; 0.2%~0.8% F; 0~0.4% Fe2O3; 0~0.3% Na2O + K2O; 0.1%~2.4% TiO2; 0.2%~1.8% CeO2; 0.5%~2.5% Y2O3; and 0.3%~2.0% La2O3. The CaO + MgO content is 9%~14.1%, the CeO2 + Y2O3 + La2O3 content is 1.4%~3.3%, and the TiO2 + Y2O3 + La2O3 ratio is 1.5~3.2%.

[0056] This invention provides a glass fiber prepared from the glass fiber composition described in any one of the above technical solutions.

[0057] The glass fiber described in this invention has a dielectric constant ≤ 6.0 and a dielectric loss ≤ 0.005.

[0058] The present invention provides a method for preparing glass fiber, comprising: forming the glass fiber composition described in any one of the above technical solutions into a fiber by a drawing process.

[0059] The glass fibers of this invention can be prepared using either a tank furnace method or an electric melting furnace method. The specific process steps are as follows:

[0060] Raw material ratio calculation: Accurately calculate the addition ratio of each raw material according to the formula requirements of the target glass;

[0061] Batch preparation: According to the calculated proportions, various raw materials are quantitatively fed into the mixing equipment, and after thorough mixing, a uniform batch is obtained;

[0062] Melting and clarification: The batch material is transported to the kiln head hopper of the pool furnace or electric melting furnace, and fed into the furnace at a uniform speed through the feeding device. The melting, clarification and homogenization process is completed at a high temperature of 1300-1500℃ to form a uniform glass melt.

[0063] Fiber drawing: After the molten glass is cooled to the forming temperature through the working channel, it is extruded through a platinum spindle to form glass wires, which are then drawn into glass fibers of a set diameter by a high-speed drawing machine.

[0064] Post-processing and finished product preparation:

[0065] After being spray-cooled, coated with a sizing agent, and bundled, the fibers are wound into a filament cake;

[0066] The silk cake can be further processed through warping, twisting, and weaving to produce electronic fabrics of different specifications;

[0067] Alternatively, continuous glass fiber yarn can be obtained through drying, descaling, and packaging processes.

[0068] It can also be sent to a chopped fiber production line to be cut into chopped filaments of the required length, and then processed through granulation, drying and screening to produce chopped glass fiber yarn.

[0069] This invention provides a composite material comprising a resin and the glass fiber described in the above-described technical solution;

[0070] The resin includes thermosetting resin or thermoplastic resin.

[0071] In this invention, the thermosetting resin includes epoxy resin, unsaturated polyester resin or polyurethane resin; the thermoplastic resin includes polycarbonate (PC), polypropylene (PP), polyamide (PA), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polystyrene (PS), polyphenylene sulfide (PPS), polyoxymethylene (POM) or polymethyl methacrylate (PMMA).

[0072] The present invention provides a circuit board material comprising the glass fiber described in the above technical solution.

[0073] The electronic-grade low-dielectric glass fiber composition provided by this invention comprises the following components by mass percentage: 54%~60% SiO2; 12%~18% Al2O3; 5~14.9% CaO; 0.2%~3.0% MgO; 5.6%~14.5% B2O3; 0~2.0% F; 0~0.4% Na2O + K2O; 0~0.5% Fe2O3; 0.1~3% TiO2; 0~3.5% Y2O3; 0~3.5% La2O3; and 0~3.0% CeO2. This glass fiber has a dielectric constant ≤5.5, a dielectric loss ≤0.004 (at 10GHz), a molding temperature not exceeding 1300℃, a molding range greater than 50℃, and can be mass-produced in a 10,000-ton-class furnace.

[0074] The electronic-grade low dielectric loss glass fiber composition and composite material of the present invention have the following advantages compared with the prior art:

[0075] (1) Lower dielectric constant and dielectric loss: The dielectric constant of the glass fiber of the present invention is ≤5.5 and the dielectric loss is ≤0.004 (at 10GHz frequency), which is more than 30% lower than that of ordinary E glass fiber. Therefore, the printed circuit board made of the glass fiber of the present invention has better dielectric performance and can better meet the needs of high frequency and high speed communication.

[0076] (2) More stable electrical properties: By adding a small amount of high field strength ions to the glass composition and controlling the ratio of TiO2+Y2O3+La2O3, the glass of the present invention can achieve a lower dielectric constant and dielectric loss with only a lower content of B2O3. At the same time, it effectively overcomes the problem of poor composition uniformity and difficulty in stable control of product electrical properties caused by excessive B2O3 content in existing LDK glass.

[0077] (3) Excellent mechanical properties: The glass fiber of the present invention contains a high content of silicon and aluminum as well as a certain proportion of TiO2, Y2O3 and La2O3, the glass network structure is more compact, and the elastic modulus reaches more than 84GPa.

[0078] (4) Lower production difficulty: The glass fiber forming temperature (temperature when the viscosity is 1000 poise) of the present invention does not exceed 1300℃ and the crystallization temperature is lower than 1200℃, which is comparable to the production difficulty of ordinary glass fiber. Stable mass production of ultrafine electronic yarn can be achieved on existing 10,000-ton-level pool furnaces. Detailed Implementation

[0079] This invention provides an electronic-grade low-dielectric glass fiber composition, glass fiber, and a method for preparing the same. Those skilled in the art can refer to the content of this document and appropriately modify the process parameters to achieve the desired results. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and fall within the scope of this invention. The methods and applications of this invention have been described through preferred embodiments. Those skilled in the art can clearly modify or appropriately change and combine the methods and applications described herein without departing from the content, spirit, and scope of this invention to realize and apply the technology of this invention.

[0080] It should be understood that the expression “one or more of…” individually includes each of the objects described after the expression, as well as various different combinations of two or more of the described objects, unless otherwise understood from the context and usage. The expression “and / or” combined with three or more described objects should be understood to have the same meaning, unless otherwise understood from the context.

[0081] The terms “including,” “having,” or “containing,” including the use of their grammatical synonyms, should generally be understood as open-ended and non-restrictive, for example, not excluding other unstated elements or steps, unless otherwise specifically stated or understood from the context.

[0082] In this application, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural.

[0083] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items.

[0084] It should be understood that the order of the steps or the order in which certain actions are performed is not important as long as the invention remains operational. Furthermore, two or more steps or actions can be performed simultaneously.

[0085] The use of any and all instances or exemplary language such as “e.g.” or “including” in this document is merely intended to better illustrate the invention and is not intended to limit the scope of the invention unless the claims are made. No language in this specification should be construed as indicating that any unclaimed element is essential to the practice of the invention.

[0086] Furthermore, the numerical ranges and parameters used to define the present invention are approximate values, and the relevant values ​​in the specific embodiments have been presented as precisely as possible. However, any value inevitably contains standard deviations due to individual test methods. Therefore, unless explicitly stated otherwise, it should be understood that all ranges, quantities, values, and percentages used in this disclosure are modified with the word "approximately". Here, "approximately" generally means that the actual value is within plus or minus 10%, 5%, 1%, or 0.5% of a specific value or range.

[0087] It should be understood that in the various embodiments of this application, the order of the above processes does not imply the order of execution. Some or all steps may be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0088] The embodiments and comparative examples of this invention describe some examples, in which the embodiments illustrate certain implementations of the invention. However, this does not mean that the effects of the invention can only be achieved in these examples.

[0089] To further illustrate the present invention, the following detailed description, in conjunction with embodiments, describes an electronic-grade low-dielectric glass fiber composition, glass fiber, and its preparation method provided by the present invention.

[0090] Examples 1-23

[0091] The examples were prepared according to the following method:

[0092] The required proportions of raw materials (quartz powder, kaolin, boron anhydride, quicklime, lightly calcined powder, fluorite, cerium oxide, yttrium oxide, and lanthanum oxide) are calculated based on the actual glass formula. Each raw material is precisely weighed according to this proportion and transported to the mixing silo for thorough and uniform mixing to obtain a qualified batch. The batch is then transported to the kiln head silo of the experimental electric melting furnace and fed into the furnace at a uniform speed by a feeder. The batch is heated, melted, clarified, and homogenized at approximately 1550℃ in the tank furnace to form a qualified glass melt. The uniform glass melt is cooled to approximately 1300℃ through the working channel and then flows out through a platinum perforator (800 holes) to form glass fibers. These glass fibers are rapidly drawn into glass fibers of a set diameter (7μm) under high-speed traction by a drawing machine. After spray cooling, coating with a sizing agent, and bundling, they are wound into a fiber cake by the drawing machine and dried to obtain a glass fiber sample. The forming temperature and crystallization limit temperature of the glass samples were tested using a high-temperature viscometer and a crystallization gradient furnace. The dielectric constant and dielectric loss of the glass samples were tested using the split resonant cavity method.

[0093] Tables 1, 2, and 3 show the formulation composition and properties of the glass fiber in Examples 1-23 of the present invention, with values ​​representing mass percentages. Due to factors such as testing errors, omission of trace impurities, and decimal places, the total percentage content of the components listed in the tables may not all reach 100%.

[0094] Where T logη=3 This indicates the temperature at which the glass viscosity reaches 1000 poise, equivalent to the temperature of the molten glass during glass fiber forming; it is also known as the "glass fiber forming temperature". 液 ΔT represents the glass liquidus temperature, which is the temperature at which the glass crystallization rate is zero. It is the upper limit of the glass crystallization temperature and is often simply referred to as the "glass fiber crystallization temperature." logη=3 With T 液 The difference represents the process window for glass fiber drawing and forming. Typically, when producing electronic yarn, ΔT should be greater than 80°C to meet the requirements for stable operation.

[0095] The high-temperature viscosity of the glass fiber was measured using a BROOKFIELD high-temperature viscometer manufactured by ORTON, the liquidus temperature of the glass was measured using an Orton Model gradient furnace, the dielectric constant and dielectric loss of the glass were determined according to GB / T 7265.1 standard, and the elastic modulus of the glass fiber was determined according to ASTM D2343-17 standard.

[0096] Table 1

[0097]

[0098] Table 2

[0099]

[0100] Table 3

[0101]

[0102] Table 4

[0103]

[0104] Table 4 shows the comparative examples. In Comparative Example 1, when the alkali content (K2O+Na2O) increased, the dielectric constant and dielectric loss of the glass increased significantly, and the dielectric properties deteriorated significantly. In Comparative Example 2, when the SiO2 content in the glass was too high, the glass forming temperature increased significantly, and the production difficulty increased dramatically. In Comparative Example 3, when the CaO content was too low and the MgO content was too high, the upper limit temperature of glass crystallization increased significantly, and the production difficulty increased. In Comparative Example 4, when CeO2, Y2O3, and La2O3 were not added to the glass composition at all, the dielectric properties of the glass deteriorated to a certain extent, and the elastic modulus decreased significantly. Comparative Examples 5 and 6 are typical compositions of boron-free and fluorine-free glass and E glass, respectively.

[0105] As shown in Tables 1-3, the glass fiber of the present invention has a lower dielectric constant and dielectric loss (dielectric constant of glass fiber ≤5.5, dielectric loss ≤0.0040 at 10GHz frequency) and a lower molding difficulty. The molding temperature does not exceed 1200℃, the molding range is greater than 80℃, the elastic modulus is greater than 84GPa, and it can be mass-produced in a 10,000-ton-level pool furnace.

[0106] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An electronic-grade low dielectric loss glass fiber composition, characterized in that, Including the following components by weight percentage: 54%~60% SiO2; 12%~18% Al2O3; 5-14.9% CaO; 0.2%~3.0% MgO; 5.6%~14.5% B2O3; 0~2.0% F; 0~0.4% Na₂O + K₂O; 0~0.5% Fe2O3; 0.1%~3% TiO2; 0~3.5% Y2O3; 0~3.5% La2O3; 0~3.0% CeO2.

2. The composition according to claim 1, characterized in that, The CaO+MgO content is 8.6%~15.9%, the CeO2+Y2O3+La2O3 content is 0-3.8%, and the TiO2+Y2O3+La2O3 ratio is 0.5~4%.

3. The composition according to claim 1, characterized in that, The electronic-grade low-dielectric glass fiber composition comprises: 55.2%~60% SiO2; 13%~17% Al2O3; 5.8%~14.2% CaO; 0.5%~2.8% MgO; 7.5%~14.3% B2O3; 0~1.2% F; 0~0.5% Fe2O3; 0~0.4% Na2O + K2O; 0.1%~2.4% TiO2; 0.2%~2.0% CeO2; 0.5%~3.0% Y2O3; 0.3%~3.0% La2O3; and the CaO + MgO content is 9%~15.1%, the CeO2 + Y2O3 + La2O3 content is 1.1%~3.5%, and the TiO2 + Y2O3 + La2O3 ratio is 1.5%~3.5%.

4. The composition according to claim 3, characterized in that, The electronic-grade low-dielectric glass fiber composition comprises: 56.5%~59.5% SiO2; 13.2%~16.4% Al2O3; 6.2%~12.8% CaO; 0.5%~2.5% MgO; 9.5%~13.5% B2O3; 0.2%~0.8% F; 0~0.4% Fe2O3; and 0~0.3% Na2O + K2. O; 0.1%~2.4% TiO2; 0.2%~1.8% CeO2; 0.5%~2.5% Y2O3; 0.3%~2.0% La2O3; and CaO+MgO content is 9%~14.1%, CeO2+Y2O3+La2O3 content is 1.4%~3.3%, and TiO2+Y2O3+La2O3 ratio is 1.5~3.2%.

5. A type of glass fiber, characterized in that, It is prepared from the glass fiber composition according to any one of claims 1 to 4.

6. The glass fiber according to claim 5, characterized in that, The dielectric constant of the glass fiber is ≤5.5, and the dielectric loss is ≤0.

004.

7. A method for preparing glass fiber, characterized in that, include: The glass fiber composition according to any one of claims 1 to 4 is formed by a drawing process.

8. A composite material, characterized in that, Includes resin and the glass fiber as described in claim 5; The resin includes thermosetting resin or thermoplastic resin.

9. The composite material according to claim 8, characterized in that, The Thermosetting resins include epoxy resins, unsaturated polyester resins, or polyurethane resins; Thermoplastic resins include polycarbonate (PC), polypropylene (PP), polyamide (PA), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polystyrene (PS), polyphenylene sulfide (PPS), polyoxymethylene (POM), or polymethyl methacrylate (PMMA).

10. A circuit board, characterized in that, The raw material includes the glass fiber as described in claim 5.

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