Method for preparing silica powder filler

Abstract

The present invention relates to a method for preparing a silica powder filler, which includes the steps of dispersing a high dielectric constant powder in a water-containing solution, adding R1SiX3 to the water-containing solution to hydrolyze and condense the polysiloxane powder, the polysiloxane powder being a polysiloxane containing T units containing high dielectric constant powder therein, and the particle size of the high dielectric constant powder being smaller than the particle size of the polysiloxane; and calcining the polysiloxane powder in an oxygen gas-containing atmosphere, the calcination temperature being between 850 degrees and 1200 degrees, to obtain a silica powder filler containing high dielectric constant powder therein. The present invention further provides a silica powder filler obtained by the above preparation method and its use. According to the preparation method of the silica powder filler of the present invention, a silica powder filler containing high dielectric constant powder therein can be obtained, and the silica powder filler has a high dielectric constant due to the inclusion of high dielectric constant powder therein, and satisfies the requirements of small communication devices.

Description

[Technical field]

[0001] The present invention relates to circuit board and antenna packaging, and more particularly to a method for preparing a silica powder filler, the powder filler obtained thereby and its uses. [Background technology]

[0002] In the field of 5G communications, when assembling wireless high-frequency devices into equipment, it is necessary to use circuit boards such as high density interconnect boards (HDI), high-frequency high-speed boards and motherboards. These circuit boards are generally made of organic polymers and fillers, such as epoxy resins, aromatic polyethers, and fluororesins, where the filler is mainly prismatic or spherical silica, whose main function is to reduce the thermal expansion coefficient of the organic polymer. Existing fillers select spherical or prismatic silica for tight packing and gradation.

[0003] With the advancement of technology, communication devices are becoming smaller and smaller. The antennas essential for communication devices are also becoming smaller and smaller, and antenna-in-package (AIP) will be used in the future. For design reasons, the substrate and packaging materials used to miniaturize antennas must have high dielectric constant and low dielectric loss, but existing known fillers cannot meet this requirement. Summary of the Invention [Problem to be solved by the invention]

[0004] In order to solve the problems such as the dielectric constant of the known fillers in the above prior art cannot meet the requirements of small communication devices, the present invention provides a method for preparing a silica powder filler, the powder filler obtained thereby and its use. [Means for solving the problem]

[0005] The method for preparing a silica powder filler of the present invention includes the following steps: S1, dispersing a high dielectric constant powder in a water-containing solution, and adding R1SiX3 to the water-containing solution to hydrolyze and condense to obtain a polysiloxane powder, the polysiloxane powder being a polysiloxane containing T units with a high dielectric constant powder therein, where R1 is a hydrogen atom or an independently selectable organic group having 1 to 18 carbon atoms, X is a group that can be decomposed by hydrolysis, the T units are R1SiO3-, and the particle size of the high dielectric constant powder is smaller than that of the polysiloxane; and S2, calcining the polysiloxane powder in an oxygen gas-containing atmosphere, the calcination temperature is between 850°C and 1200°C, to obtain a silica powder filler containing a high dielectric constant powder therein.

[0006] Preferably, the particle size of the high dielectric constant powder is not more than one-third the particle size of the polysiloxane.

[0007] Preferably, R1SiX3 is methyltrimethoxysilane.

[0008] Preferably, the high dielectric constant powder is at least one selected from the group consisting of titanium oxide, zinc oxide, zirconium oxide, titanates, zincates, zirconates, etc. In a preferred embodiment, the high dielectric constant powder is barium titanate, titanium oxide, or calcium titanate.

[0009] Preferably, the water-containing solution in step S1 is a water-based solution. Preferably, the weight percentage of water in the water-containing solution is between 80% and 100%. In a preferred embodiment, the water-containing solution is deionized water.

[0010] Preferably, the calcination temperature is between 850° C. and 1100° C., and the calcination time is between 6 hours and 12 hours.

[0011] Preferably, the polysiloxane further comprises Q, D, and / or M units, where Q units = SiO4-, D units = R2R3SiO2-, and M units = R4R5R6SiO2-, and R2, R3, R4, R5, and R6 are each independently selectable organic groups having 1 to 18 carbon atoms.

[0012] Preferably, the T unit raw material R1SiX3 of the polysiloxane is at least one selected from the group consisting of methyltrimethoxysilane, hydrocarbyltrihydrocarbyloxysilane, methyltrichlorosilane, and hydrocarbyltrichlorosilane, the Q unit raw material is at least one selected from the group consisting of tetrahydrocarbyloxysilane, silicon tetrachloride, and silica, the D unit raw material is at least one selected from the group consisting of dihydrocarbyldihydrocarbyloxysilane and dihydrocarbyldichlorosilane, and the M unit raw material is at least one selected from the group consisting of trihydrocarbylhydrocarbyloxysilane, trihydrocarbylchlorosilane, and hexahydrocarbyldisilazane. In a preferred embodiment, the R1SiX3 silane is methyltrimethoxysilane, the Q unit source is tetraethoxysilane, and the D unit source is dimethyldichlorosilane.

[0013] Preferably, the polysiloxane is a spherical or angular polysiloxane.

[0014] Preferably, the preparation method further comprises the step of performing a surface treatment on the silica powder filler by adding a treatment agent, the treatment agent comprising a silane coupling agent and / or a disilazane; the silane coupling agent is (R7) a (R8) b Si(M) 4-a-b wherein R7 and R8 are independently selectable hydrocarbon groups having 1 to 18 carbon atoms, hydrogen atoms, or hydrocarbon groups having 1 to 18 carbon atoms substituted with a functional group, the functional group being at least one selected from the group consisting of the following organic functional groups: vinyl groups, allyl groups, styryl groups, epoxy groups, aliphatic amino groups, aromatic amino groups, methacryloxypropyl groups, acryloxypropyl groups, ureidopropyl groups, chloropropyl groups, mercaptopropyl groups, polysulfide groups, and isocyanatopropyl groups; M is an alkoxy group having 1 to 18 carbon atoms or a halogen atom, a=0, 1, 2, or 3, b=0, 1, 2, or 3, and a+b=1, 2, or 3; and the disilazane is selected from the group consisting of (R9R 10 R 11 )SiNHSi(R 12 R 13 R 14 ), R9, R 10 , R 11 , R 12 , R 13 , R 14 is an independently selectable hydrocarbon group having 1 to 18 carbon atoms or a hydrogen atom.

[0015] The present invention further provides a silica powder filler obtained by the above preparation method, which contains a high dielectric constant powder inside the silica powder filler.

[0016] Preferably, the volume fraction of the high dielectric constant powder in the polysiloxane powder is between 5% and 95%, and the average particle size of the silica powder filler is between 0.5 μm and 50 μm. In a preferred embodiment, the volume fraction of the high dielectric constant powder in the polysiloxane powder is between 10% and 60%, and the average particle size of the silica powder filler is between 1.2 μm and 5.8 μm.

[0017] The present invention further provides the use of said silica powder filler, intimately packing and grading silica powder fillers with different particle sizes into resin to form composite materials suitable for circuit board materials and semiconductor packaging materials.

[0018] Preferably, the use involves removing coarse particles of 1 μm, 3 μm, 5 μm, 10 μm, 20 μm or more from the silica powder filler using dry or wet sieving or inertial classification. Effect of the Invention

[0019] According to the preparation method of silica powder filler of the present invention, silica powder filler containing high dielectric constant powder inside can be obtained, and by containing high dielectric constant powder inside, it has high dielectric constant, and meets the requirements of small communication equipment.In particular, because high dielectric constant powder is coated inside silica, its own high surface activity performance and the property that cannot be coupled with silane coupling agent do not affect the affinity between silica powder filler and resin, and meets the requirements of circuit board and antenna packaging. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a schematic diagram of a silica powder filler according to Example 1 of the present invention.

[0021] [Diagram 2] FIG. 2 is a schematic diagram of a silica powder filler according to Example 2 of the present invention.

[0022] [Diagram 3] FIG. 2 is a schematic diagram of a silica powder filler according to Example 3 of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Hereinafter, preferred embodiments of the present invention will be provided and described in detail in conjunction with the accompanying drawings.

[0024] The detection method according to the embodiment includes the following:

[0025] The average particle size is measured by a laser particle size analyzer LA-700 manufactured by HORIBA.

[0026] The geometric structure of the powder is determined by electron microscope observation and EDX elemental analysis. Specifically, the powder is mixed with epoxy resin and cured. The cured product is sliced ​​and then the surface is polished, and the cross-section of the polished particle is observed under an electron microscope, and the components of various fields are determined by EDX elemental analysis. The results are characterized by a schematic diagram.

[0027] Volume fraction of high dielectric constant powder in polysiloxane powder = (weight of high dielectric constant powder / specific gravity of high dielectric constant powder) / (weight of high dielectric constant powder / specific gravity of high dielectric constant powder + weight of polysiloxane / specific gravity of polysiloxane). The specific gravity of polymethylsiloxane (also called polymethylsilsesquioxane) is 1.34.

[0028] As used herein, average particle size refers to the volume average diameter of the particles.

[0029] Example 1

[0030] At room temperature, take a certain weight part of deionized water, disperse commercially available barium titanate with an average particle size of 0.3 μm in the water, put it into a reaction kettle equipped with a stirrer, start stirring, add 80 weight parts of methyltrimethoxysilane and stir for 1 hour. After dissolving the methyltrimethoxysilane, add 25 weight parts of 5% ammonia water and stir for 10 seconds, then stop stirring. After standing for 1 hour, filter and dry to obtain spherical powder. The powder is put into a muffle furnace and gradually heated, and organic matter is discharged under an oxygen gas-containing atmosphere, and the temperature is raised to 1000 degrees and calcined for 6 hours to obtain spherical barium titanate-containing silica powder. The analysis results of the sample are shown in Table 1 below.

[0031] [Table 1]

[0032] The results of the electron microscope and EDX analysis of Examples 1 to 3 are shown in FIG. 1, which shows that barium titanate is coated inside the silica.

[0033] Example 2

[0034] At room temperature, take a certain weight part of deionized water, disperse commercially available titanium oxide with an average particle size of 0.38 μm in the water, put it into a reaction kettle equipped with a stirrer, start stirring, add 75 weight parts of methyltrimethoxysilane and 5 weight parts of tetraethoxysilane and stir for 1 hour. After dissolving methyltrimethoxysilane and tetraethoxysilane, add 25 weight parts of 5% ammonia water and stir for 10 seconds before stopping stirring. Leave it for 1 hour, filter and dry to obtain powder. Put the powder into a muffle furnace and gradually increase the temperature, discharge organic matter under an oxygen gas-containing atmosphere, and increase the temperature to 850 degrees and calcinate for 12 hours to obtain titanium oxide-containing silica powder. The analysis results of the sample are shown in Table 2 below.

[0035] [Table 2]

[0036] The results of the electron microscope and EDX analysis of Example 4 are shown in FIG. 2, which shows that titanium oxide is coated inside the silica.

[0037] Example 3

[0038] At room temperature, take a certain weight part of deionized water, disperse commercially available calcium titanate with an average particle size of 2 μm in the water, put it into a reaction kettle equipped with a stirrer, start stirring, add 78 weight parts of methyltrichlorosilane and 2 weight parts of dimethyldichlorosilane, and stir for 1 hour. The volume fraction of calcium titanate is 30%. The contents are filtered, washed with water, and then dried. The white solid is pulverized with a grinder to obtain a square powder with an average particle size of 50. The powder is put into a muffle furnace and gradually heated, and organic matter is discharged under an oxygen gas-containing atmosphere, and the temperature is raised to 1000 degrees and calcined for 12 hours to obtain the calcium titanate-containing square silica powder of Example 5. The average particle size of the sample is 42 μm. As a result of electron microscope and EDX analysis, the structure of Example 5 is as shown in FIG. 3.

[0039] It should be understood that the samples of the examples obtained in the above Examples 1 to 5 can be subjected to a surface treatment. Specifically, if necessary, a treatment such as a vinyl silane coupling agent, an epoxy silane coupling agent, or a disilazane can be performed. If necessary, one or more treatments can be performed.

[0040] It will be appreciated that the preparation method includes removing coarse particles of 1, 3, 5, 10, 20 μm or larger from the filler using dry or wet sieving or inertial classification.

[0041] It is to be understood that spherical silica powder fillers of different particle sizes are intimately packed and graded into the resin to form the composite material.

[0042] The above is only a preferred embodiment of the present invention, and does not limit the scope of the present invention. Various modifications can be made to the above embodiment of the present invention. That is, all simple and equivalent changes and modifications made according to the claims and the contents of the specification of the present invention are included in the patent protection scope of the present invention. The contents not described in detail in the present invention are prior art contents.

Claims

1. 1. A method for preparing a silica powder filler comprising the steps of: The preparation method includes the following steps: S1, high dielectric constant powder is dispersed in a water-containing solution; １ Six ３ is added to a water-containing solution to be hydrolyzed and condensed to provide a polysiloxane powder, the polysiloxane powder being a polysiloxane containing T units containing a high dielectric constant powder therein, wherein R １ are hydrogen atoms or independently selectable organic groups having 1 to 18 carbon atoms, X is a hydrolyzable group, and the T units are R １ SiO ３ and the particle size of the high dielectric constant powder is smaller than the particle size of the polysiloxane; and S2, calcining the polysiloxane powder in an oxygen gas-containing atmosphere, the calcination temperature being between 850°C and 1200°C, to obtain a silica powder filler containing high dielectric constant powder therein; The particle size of the high dielectric constant powder is one-third or less of the particle size of the polysiloxane.

2. The method for preparing the silica powder filler according to claim 1 ,

2. The high dielectric constant powder is characterized in that at least one is selected from the group consisting of titanium oxide, zinc oxide, zirconium oxide, titanates, zincates, and zirconates.

2. The method of claim 1.

3. The calcination temperature is between 850°C and 1100°C, and the calcination time is between 6 hours and 12 hours.

2. The method of claim 1.

4. The polysiloxane further comprises Q units, D units, and / or M units, where Q units=SiO ４ - and D unit = R ２ R ３ SiO ２ -, and M unit = R ４ R ５ R ６ SiO ２ - and R ２ , R ３ , R ４ , R ５ , R ６ are each independently selectable organic groups having a hydrogen atom or 1 to 18 carbon atoms.

2. The method of claim 1.

5. Polysiloxane T unit raw material R １ Six ３ is at least one selected from the group consisting of methyltrimethoxysilane, hydrocarbylhydrocarbyloxysilane, methyltrichlorosilane, and hydrocarbyltrichlorosilane; the Q unit raw material is at least one selected from the group consisting of tetrahydrocarbyloxysilane, silicon tetrachloride, and silica; the D unit raw material is dihydrocarbyldihydride. At least one selected from the group consisting of dihydrocarbyloxysilane and dihydrocarbyldichlorosilane, and the M unit raw material is at least one selected from the group consisting of trihydrocarbylhydrocarbyloxysilane, trihydrocarbylchlorosilane and hexahydrocarbyldisilazane.

5. The method of claim 4.

6. The preparation method further includes a step of performing a surface treatment on the silica powder filler by adding a treatment agent, the treatment agent including a silane coupling agent and / or a disilazane; the silane coupling agent is (R ７ ) ａ (R ８ ) ｂ Si(M) ４－ａ－ｂ and R ７ and R ８ are independently selectable hydrocarbon groups having 1 to 18 carbon atoms, hydrogen atoms, or hydrocarbon groups having 1 to 18 carbon atoms substituted with a functional group, the functional group being at least one selected from the group consisting of the following organic functional groups: vinyl groups, allyl groups, styryl groups, epoxy groups, aliphatic amino groups, aromatic amino groups, methacryloxypropyl groups, acryloxypropyl groups, ureidopropyl groups, chloropropyl groups, mercaptopropyl groups, polysulfide groups, and isocyanatopropyl groups; M is an alkoxy group having 1 to 18 carbon atoms or a halogen atom, a=0, 1, 2, or 3, b=0, 1, 2, or 3, and a+b=1, 2, or 3; the disilazane is represented by (R ９ R １０ R １１ )SiNHSi(R １２ R １３ R １４ ) and R ９ , R １０ , R １１ , R １２ , R １３ , R １４ is an independently selectable hydrocarbon group having 1 to 18 carbon atoms or a hydrogen atom; 2. The method of claim 1.

Images