Calcium titanate particle material, method for producing same, slurry composition, and resin composition

Abstract

The present invention addresses the problem of providing a calcium titanate particle material in which changes in chromaticity due to irradiation with ultraviolet light are suppressed. This calcium titanate particle material has a circularity of 0.8 or more, a volume average particle diameter ([mu] m), and a specific surface area (b (m2 / g)), a being 0.1-8, and ab being less than 4. With this configuration, the relationship between the volume average particle diameter and the specific surface area can be rationalized, and as a result, the change in chromaticity over time can be suppressed.

Description

TECHNICAL FIELD

[0001] The present application relates to a calcium titanate particle material, a manufacturing method thereof, a slurry composition, a resin composition, and particularly to a calcium titanate particle material and a manufacturing method thereof, a slurry composition in which the calcium titanate particle material is dispersed, and a resin composition. BACKGROUND

[0002] In recent years, driving at high speed and high frequency of electronic devices is progressing. Therefore, reduction of transmission loss of electronic device materials such as a substrate material, a sealing material, and the like becomes an important issue. The dielectric loss tangent (Df) greatly affects the magnitude of the transmission loss, and the transmission loss can be reduced by using a material having a low Df.

[0003] For electronic device materials, there are uses that require materials having a high dielectric constant (Dk), but materials having a high Dk tend to have a high Df, and it is required to reduce the Df to reduce the transmission loss. As a material that can achieve a high Dk and a low Df with high possibility, there is calcium titanate (Patent Literature 1).

[0004] PRIOR ART DOCUMENT

[0005] PATENT LITERATURE

[0006] Patent Literature 1: International Publication No. 2022 / 124396 SUMMARY

[0007] However, if the calcium titanate is exposed to ultraviolet rays, it is colored. Therefore, for a resin composition in which a particle material composed of calcium titanate is dispersed in a resin material, a case where the color tone changes over time and the appearance gradually changes becomes a problem.

[0008] The present application was completed in view of the above-described actual situation, and to provide a calcium titanate particle material, a manufacturing method thereof, a slurry composition, and a resin composition in which a change in color tone caused by irradiation of ultraviolet rays is suppressed as an issue to be solved.

[0009] The calcium titanate particle material of the present application that solves the above-described issue has a circularity of 0.8 or more,

[0010] a volume average particle diameter of a (μm) and a specific surface area of b (m 2 / g),

[0011] a is 0.1 to 8, and ab is less than 4.

[0012] The manufacturing method of the calcium titanate particle material of the present application that solves the above-described issue has a spheroidization process of feeding a raw particle material in which calcium titanate is a main component in a state of being dispersed in a carrier into a high-temperature atmosphere.

[0013] The slurry composition of the present application, which solves the above problems, has the calcium titanate particle material of the present application and a dispersion medium that is a liquid substance that disperses the above calcium titanate particle material.

[0014] The resin composition of the present application, which solves the above problems, has the calcium titanate particle material of the present application and a resin material that disperses the above calcium titanate particle material.

[0015] The calcium titanate particle material of the present application, by having the above configuration, can rationalize the relationship between the volume average particle diameter and the specific surface area, and as a result, can suppress the change in color tone over time. DETAILED DESCRIPTION

[0016] Hereinafter, the calcium titanate particle material of the present application will be described in detail according to the embodiments. The calcium titanate particle material of the present embodiment can be suitably used as a material for electronic devices. As the electronic device that is a preferred specific application, a package antenna can be exemplified, and it is preferably used in the form of a slurry composition or a resin composition. As the resin composition, a prepreg, a copper-clad laminate, a film can be exemplified. Note that in the present specification, the range of a numerical value written as a to b includes the values of a and b. In addition, it can be formed by modifying the range not including a and b. Also, in the present specification, in the case where a numerical value is described, a numerical range in which a value arbitrarily selected from among these numerical values is combined as an upper limit and a lower limit can be adopted. In addition, an arbitrary value can be selected from among these numerical values, and the value can be adopted as an upper limit or a lower limit. The value adopted as an upper limit or a lower limit can be included in the set range or can not be included in the set range. Furthermore, it can be that one of the upper limit and the lower limit is included in the range and the other is not included in the range.

[0017] (Calcium titanate particle material)

[0018] In the calcium titanate particle material of the present embodiment, calcium titanate is the main component. The calcium titanate being the main component means that the lower limit value of the amount of calcium titanate is 50% by mass, and means that the lower limit value is preferably 60% by mass, 70% by mass, 80% by mass, 90% by mass, 95% by mass, 99% by mass, 100% by mass (impurities or trace amounts of impurities that cannot be avoided can be included). As a compound that can be contained other than calcium titanate, there are iron oxide, molybdenum oxide, and silicon dioxide. The impurities can be contained in the crystal of calcium titanate, or can be contained in the form of independent particles.

[0019] Since the silicon dioxide further suppresses coloring, it is particularly preferable to contain silicon dioxide. The upper limit value of the content of the silicon dioxide can be exemplified by 10 mass%, 7.5 mass%, 5.0 mass%, and the lower limit value can be exemplified by 1.0 mass%, 2.0 mass%, 3.0 mass%. These upper and lower limit values can be combined arbitrarily. By making the content of the silicon dioxide be the lower limit value or more, coloring can be sufficiently suppressed, and by making it be the upper limit value or less, improvement of the dielectric properties such as improvement of the dielectric constant can be achieved.

[0020] The content of the silicon dioxide can be set to the above range based on the mass of the entire calcium titanate particle material, and it is particularly preferable that the amount of the silicon dioxide be within the range of these upper and lower limit values on the surface of the calcium titanate particle material.

[0021] In particular, by making the silicon dioxide exist on the surface, the amount of the ultraviolet reaching the calcium titanate can be reduced. Specifically, it is further preferable that the content of the silicon dioxide measured by energy dispersive X-ray analysis (EDX) be included in the above upper and lower limit values. EDX is a measurement method in which the measured value is particularly dependent on the atomic composition of the surface.

[0022] The circularity of the calcium titanate particle material of the present embodiment is 0.8 or more, preferably 0.85 or more, more preferably 0.9 or more, further preferably 0.95 or more, and particularly preferably 0.99 or more.

[0023] The circularity is calculated as a value obtained by photographing a photograph with SEM, and calculating from the area and the circumference of the particle observed from the photograph using (circularity) = {4π x (area) ÷ (circumference) 2}. The closer to 1, the closer to a true sphere. Specifically, the average value obtained by measuring 100 particles using an image processing device (Sysmex Corporation: FPIA-3000) is used.

[0024] The calcium titanate particle material of the present embodiment has a volume average particle diameter of a (μm) and a specific surface area of b (m 2 / g). a is 0.1 to 8. As a lower limit value of a, 0.2, 0.3 is more preferable, and 7.0, 6.0, 5.5, 5.0, 4.0, 2.5 is preferable. If a is the lower limit value or more, dispersibility in a slurry composition such as varnish is improved, and if it is the upper limit value or less, the settling speed is reduced, and the possibility of separation is less.

[0025] The upper limit of b is preferably 2.2, 2.0, 1.8, or 1.5, and the lower limit is preferably 0.1, 0.2, or 0.4. ab is less than 4. The upper limit of ab is preferably 4.0, 3.5, 3.0, 2.5, or 2.0. The upper and lower limits of each of a, b, and ab can be combined arbitrarily.

[0026] The moisture content of the calcium titanate particle material in this embodiment is preferably 800 ppm or less. The upper limit of the moisture content is further preferably 700 ppm, 600 ppm, 500 ppm, 400 ppm, or 300 ppm. The moisture content is determined by the Karl Fischer method. By reducing the moisture content, the Df value can be reduced or side reactions during dispersion in the resin can be suppressed.

[0027] In this embodiment, the Df of the calcium titanate particle material is preferably 0.016 or less, more preferably 0.015 or less, even more preferably 0.010 or less, and particularly preferably 0.008 or less.

[0028] The calcium titanate particle material of this embodiment b / a Preferably, it is 5 or higher, more preferably 5.5 or higher, and even more preferably 6.0 or higher. / a The measurement was performed using a mercury lamp at a light intensity of 11.5 KW / m². 2 The sample, after being irradiated for 72 hours on a surface with a thickness of less than 5 mm, was dispersed in a cyclohexane solution at a concentration of 33.3% by mass. The resulting dispersion was measured using a colorimeter (e.g., a Konica Minolta CM-5 spectrophotometer).

[0029] The calcium titanate particle material of this embodiment is preferably surface-treated. There are no particular limitations on the surface treatment agent, but silane compounds or silazane compounds, such as silane coupling agents, are preferred. Examples of silane compounds include those having organic functional groups such as alkyl, phenyl, amino, phenylamino, vinyl, methacrylate, and epoxy groups, either alone or in combination. Examples of silazane compounds include hexamethyldisilazane.

[0030] As a surface treatment agent, a single compound or a mixture of multiple compounds can be used. The organic functional groups can be determined according to the type of resin material and dispersion medium. There is no particular limitation on the amount of surface treatment, but it can be performed at an amount of 0.1 to 5.0 parts by mass per 100 parts by mass of calcium titanate particles.

[0031] (Manufacturing method of calcium titanate particle material)

[0032] The manufacturing method of the calcium titanate particle material of the present embodiment is a manufacturing method that can suitably manufacture the calcium titanate particle material of the present embodiment described above, and has a spheroidization step and other steps selected as necessary.

[0033] The spheroidization step is a method that can obtain a particle material with a high degree of circularity by spheroidizing the raw material particle material by heating and melting it under a high-temperature atmosphere and then rapidly cooling it. The high-temperature atmosphere is not particularly limited and is a temperature that can soften or even melt the calcium titanate.

[0034] The high-temperature atmosphere can employ a flame formed by mixing and combusting a combustible gas and a combustion-supporting gas, plasma, or the like. As the combustible gas, propane gas, acetylene gas, hydrogen, or the like can be exemplified.

[0035] The volume average particle diameter and the particle size distribution of the calcium titanate particle material obtained after the spheroidization step are controlled in accordance with the volume average particle diameter and the tendency of the particle size distribution of the raw material particle material.

[0036] As for the raw material particle material, the desired particle size distribution can be achieved by refining large particles through a pulverization operation, or by performing particleization when synthesizing the calcium titanate, or by melting the calcium titanate and performing particleization through a spray, or by other methods.

[0037] The introduction of the raw material particle material under the high-temperature atmosphere is performed in a state of dispersion in a carrier. As the carrier, a gas such as a non-active gas such as nitrogen, a combustion-supporting gas such as oxygen, a combustible gas such as propane, a liquid such as water, an alcohol such as methanol, isopropyl alcohol, a ketone such as acetone can be exemplified.

[0038] The raw material particle material is a particle material having calcium titanate as a main component, and the composition thereof is as described above for the manufactured calcium titanate, so further explanation is omitted. Here, the composition of the raw material particle material is roughly reflected in the composition of the directly manufactured calcium titanate particle material, so the composition, purity, and the like of the raw material particle material are set in accordance with the composition, purity, and the like of the calcium titanate particle material that is ultimately desired to be manufactured.

[0039] Here, as described above, when it is desired to increase only the content of silicon dioxide on the surface of the calcium titanate particle material, this can be achieved by being in a state in which a particle material composed of silicon dioxide (silicon dioxide particle material) is attached to the surface of the raw material particle material. As the silicon dioxide particle material, a particle diameter smaller than that of the raw material particle material is preferable because it can easily coat the surface of the raw material particle material. For example, as the particle diameter of the silicon dioxide particle material, a particle diameter of about 1 to 100 nm can be employed. These silicon dioxide particle materials can be surface-treated with a silane compound, a silazane compound, or the like, and can also have introduced an alkyl group such as a phenyl group, a methyl group, or the like.

[0040] The silica particle material can be mixed in a dry state or in a wet state. The mixing operation can be performed by stirring and mixing using a mixer, or by performing a pulverizing operation using a pulverizer such as a vibration mill, or in the case of mixing in a wet state, by mixing by vibrating using ultrasonic irradiation or the like.

[0041] In the case of mixing in a wet state, the raw material particle material can be supplied in the form of a slurry in which the raw material particle material and the silica particle material are dispersed in a carrier composed of a liquid, to a high-temperature atmosphere.

[0042] The concentration at which the raw material particle material is dispersed in the carrier and the speed at which the dispersion is supplied are not particularly limited, but can be set to 0.5 kg to 10 kg or so per 1 Nm3of the carrier. 3 The raw material particle material is dispersed in the carrier at a concentration of 0.5 kg to 10 kg or so per 1 Nm3of the carrier. The lower limit of the amount of the raw material particle material can be 1 kg, 2 kg, and the upper limit can be 10 kg, 8 kg, 3 kg.

[0043] The speed at which the dispersion is supplied can be 5 kg / hour to 15 kg / hour or so of the raw material particle material, although this varies depending on the size of the flame. The upper limit of the speed at which the dispersion is supplied can be 15 kg / hour, 13 kg / hour, 10 kg / hour, and the lower limit can be 5 kg / hour, 7 kg / hour, 9 kg / hour or so.

[0044] The raw material particle material can be subjected to surface treatment that can be performed on the calcium titanate particle material of the present embodiment. This has the advantage of improving flowability and the like by performing surface treatment.

[0045] (Slurry composition)

[0046] The slurry composition of the present embodiment is a slurry composition in which the calcium titanate particle material of the present embodiment is mixed with a liquid dispersion medium, and the calcium titanate particle material is dispersed in the dispersion medium. The mixing ratio of the calcium titanate particle material to the dispersion medium is not particularly limited, but preferably contains 30% or more of the calcium titanate particle material, more preferably 50% or more, and further preferably 70% or more, based on the total mass.

[0047] As the dispersion medium, in addition to liquids such as alcohols such as methanol and isopropyl alcohol, alkanes such as hexane, and ketones such as acetone, which are referred to as so-called solvents, a precursor of a resin material such as a liquid monomer, which is solidified after use and is no longer liquid, can be used. Note that whether or not the liquid is liquid is determined based on whether or not it is liquid under specific conditions that can be arbitrarily set. Thus, in the case of use at high temperatures or low temperatures, as long as the material becomes liquid at that temperature, it can be a dispersion medium. In addition, a compound dissolved in the dispersion medium can be dissolved in the dispersion medium.

[0048] The slurry composition of the present embodiment can also contain a particle material other than the calcium titanate particle material. For example, a particle material composed of an inorganic material such as silica or alumina, or a particle material composed of a resin material such as a polyolefin or a perfluoropolyolefin can also be contained.

[0049] (Resin composition)

[0050] The resin composition of the present embodiment is a resin composition formed by mixing the calcium titanate particle material of the present embodiment and a resin material, and dispersing the calcium titanate particle material in the resin material. The mixing ratio of the calcium titanate particle material to the resin material is not particularly limited, but preferably contains 80% or more of the calcium titanate particle material, more preferably 70% or more, and further preferably 60% or more, based on the total mass.

[0051] As the resin material, a precursor before curing of a thermosetting resin such as an epoxy resin or a urea-formaldehyde resin, a thermoplastic resin such as a polyolefin or a polyester, and a monomer thereof can be exemplified. If the resin material is in a liquid form, it can also belong to the resin composition of the present embodiment and the slurry composition of the present embodiment.

[0052] The resin composition of the present embodiment can also contain a particle material other than the calcium titanate particle material. For example, a particle material composed of an inorganic material such as silica or alumina, or a particle material composed of a resin material such as a polyolefin or a perfluoropolyolefin can also be contained.

[0053] Example

[0054] The calcium titanate particle material of the present invention and the method for producing the same will be described according to an example.

[0055] (Test Example 1)

[0056] A mixture of calcium titanate particles broken by a crushing operation and spherical silica was used as a raw particle material. The content of the spherical silica was 5.0% based on the total mass of the raw particle material. The particle diameter of the spherical silica was 10 nm, and the raw particle material as a mixture of the calcium titanate particles and the spherical silica was in a state in which the spherical silica was attached to the surface of the calcium titanate particles.

[0057] The raw particle material was fed into a flame formed in a furnace body at 10 kg / hour while being dispersed in a carrier of 5 Nm 3 / hour composed of nitrogen gas (spheroidization step). The flame was formed using propane gas 5 Nm 3 / hour as a combustible gas and oxygen 17 Nm 3 / hour as a combustion-supporting gas.

[0058] The raw particle material introduced into the flame is melted and spheroidized due to surface tension, and then falls from the flame and is cooled, thereby solidifying while maintaining a spherical shape. The obtained spherical calcium titanate (calcium titanate particle material) is recovered by a bag filter, a cyclone separator, or the like, and used as a test sample of the present test example.

[0059] (Test Examples 2 and 3)

[0060] Test samples of each test example were prepared by performing the spheroidization step on raw particle materials having different particle diameters of calcium titanate particles under the conditions shown in Test Example 1. The smaller the particle diameter of the calcium titanate particles, the smaller the particle diameter of the obtained test sample.

[0061] (Test Examples 4 and 5)

[0062] Test samples of Test Examples 1 and 2 were subjected to surface treatment, and used as test samples of each test example. The surface treatment was performed using KBM-1003 as a surface treatment agent.

[0063] (Test Example 6)

[0064] The raw particle material used in Test Example 1 was directly used as a test sample of the present test example.

[0065] (Test Example 7)

[0066] As a raw particle material, a spherical silica was not contained and only calcium titanate particles were used, and the same operation as in Test Example 1 was performed, and the obtained particle material was used as a test sample of the present comparative example.

[0067] (Evaluation)

[0068] The roundness, chromaticity a and b , volume average particle diameter, specific surface area, moisture content, Df, and silica concentration (Si02proportion: mass%) of the test samples of each test example were measured. These measured values and the values of b / a and volume average particle diameter x specific surface area are shown in Table 1.

[0069] The roundness, chromaticity, and moisture content were measured by the methods described in the embodiments. The volume average particle diameter was measured by a laser diffraction type particle size distribution measuring device. The specific surface area was measured by weighing 1.0 g of each test sample, introducing it into a measuring cell, and measuring the BET specific surface area value after pretreatment. The measuring machine used was "Macsorb HM model-1208" (manufactured by MACSORB). The pretreatment conditions were a degassing temperature of 200°C, a degassing time of 30 minutes, and a cooling time of 4 minutes.

[0070] Df was measured in accordance with JIS C 2138 (2007). Specifically, a network analyzer (product name "E5071C" manufactured by Keysight) and a cavity resonator perturbation method were used to measure the relative dielectric constant and the dielectric loss tangent at 1 GHz. Further, the surface concentration of silicon dioxide (Si02 ratio: mass%) was measured by EDX. The content on a mass basis was calculated from the obtained measured values.

[0071]

[0072] As is apparent from Table 1, the test samples of Test Examples 1 to 5 have a larger b / a than the test sample of Test Example 6. Further, the test samples of Test Examples 1 to 5 have a larger b

[0073] than the test samples of Test Examples 1 to 3 except that surface treatment was not performed. Although the difference is small, the test samples of Test Examples 4 and 5 have a larger b / a than the test samples of Test Examples 1 to 3. Thus, it is known that the change in the color tone can be suppressed by performing surface treatment. The test samples of Test Examples 4 and 5 have a further smaller amount of moisture and a smaller Df. Further, it is known that the test sample of Test Example 1 containing silicon dioxide has a larger b / a than the test sample of Test Example 7 not containing silicon dioxide. The test sample of Test Example 1 has a larger b

Claims

1. A calcium titanate particle material, the circularity is 0.8 or more, The volume average particle diameter is a (μm) and the specific surface area is b (m 2 / g). a is 0.1 to 8, and ab is less than 4.

2. The calcium titanate particle material according to claim 1, wherein, the moisture content is 800 ppm or less.

3. The calcium titanate particulate material of claim 1, wherein, the dielectric loss tangent is 0.016 or less.

4. The calcium titanate particulate material of claim 1, wherein, b is determined by the following measurement method / a is 5 or more, (Measurement method) The sample after irradiation of a mercury lamp of 11.5 KW / m2 for 72 hours to the surface flattened to a thickness of 5 mm or less was dispersed in a cyclohexane solution at a concentration of 33.3 mass%, and the dispersion liquid thus formed was measured with a color difference meter. 2 The sample after irradiation of a mercury lamp of 11.5 KW / m2 for 72 hours to the surface flattened to a thickness of 5 mm or less was dispersed in a cyclohexane solution at a concentration of 33.3 mass%, and the dispersion liquid thus formed was measured with a color difference meter.

5. The calcium titanate particulate material of claim 1, wherein, The content of silicon dioxide measured by energy dispersive X-ray analysis is 1 to 10 mass%.

6. The calcium titanate particulate material of claim 1, wherein, The calcium titanate particle material is surface-treated.

7. A method for producing a calcium titanate particle material, comprising a spheroidization step of feeding a raw material particle material having calcium titanate as a main component into a high-temperature atmosphere in a state of being dispersed in a carrier.

8. A slurry composition comprising the calcium titanate particle material according to any one of claims 1 to 6 and a dispersion medium as a liquid substance for dispersing the calcium titanate particle material.

9. A resin composition comprising the calcium titanate particle material according to any one of claims 1 to 6 and a resin material for dispersing the calcium titanate particle material.

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