JP7130529B2 - Method for producing porous silica - Google Patents
Method for producing porous silica Download PDFInfo
- Publication number
- JP7130529B2 JP7130529B2 JP2018217628A JP2018217628A JP7130529B2 JP 7130529 B2 JP7130529 B2 JP 7130529B2 JP 2018217628 A JP2018217628 A JP 2018217628A JP 2018217628 A JP2018217628 A JP 2018217628A JP 7130529 B2 JP7130529 B2 JP 7130529B2
- Authority
- JP
- Japan
- Prior art keywords
- silica
- particles
- sol
- porous body
- porous
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 title claims description 162
- 239000000377 silicon dioxide Substances 0.000 title claims description 50
- 238000004519 manufacturing process Methods 0.000 title claims description 6
- 239000002245 particle Substances 0.000 claims description 35
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 claims description 33
- 229910002027 silica gel Inorganic materials 0.000 claims description 17
- 239000000741 silica gel Substances 0.000 claims description 17
- BOTDANWDWHJENH-UHFFFAOYSA-N Tetraethyl orthosilicate Chemical compound CCO[Si](OCC)(OCC)OCC BOTDANWDWHJENH-UHFFFAOYSA-N 0.000 claims description 15
- 238000000034 method Methods 0.000 claims description 13
- 239000000843 powder Substances 0.000 claims description 12
- 239000000463 material Substances 0.000 claims description 11
- 239000000203 mixture Substances 0.000 claims description 6
- 238000010298 pulverizing process Methods 0.000 claims description 6
- 239000012798 spherical particle Substances 0.000 claims description 2
- 238000002834 transmittance Methods 0.000 description 13
- 239000011148 porous material Substances 0.000 description 11
- 238000009792 diffusion process Methods 0.000 description 8
- -1 silicon alkoxide Chemical class 0.000 description 7
- DNIAPMSPPWPWGF-UHFFFAOYSA-N Propylene glycol Chemical compound CC(O)CO DNIAPMSPPWPWGF-UHFFFAOYSA-N 0.000 description 6
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 5
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 4
- 239000000499 gel Substances 0.000 description 4
- 210000003739 neck Anatomy 0.000 description 4
- 238000013001 point bending Methods 0.000 description 4
- 238000001878 scanning electron micrograph Methods 0.000 description 4
- 229910052710 silicon Inorganic materials 0.000 description 4
- 239000010703 silicon Substances 0.000 description 4
- 239000002131 composite material Substances 0.000 description 3
- 238000010304 firing Methods 0.000 description 3
- 239000011521 glass Substances 0.000 description 3
- 230000003301 hydrolyzing effect Effects 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 3
- 238000001179 sorption measurement Methods 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 2
- 239000004115 Sodium Silicate Substances 0.000 description 2
- 229910021529 ammonia Inorganic materials 0.000 description 2
- 239000008119 colloidal silica Substances 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 239000010419 fine particle Substances 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 239000004570 mortar (masonry) Substances 0.000 description 2
- 230000035699 permeability Effects 0.000 description 2
- 239000011164 primary particle Substances 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 229910052911 sodium silicate Inorganic materials 0.000 description 2
- LFQCEHFDDXELDD-UHFFFAOYSA-N tetramethyl orthosilicate Chemical compound CO[Si](OC)(OC)OC LFQCEHFDDXELDD-UHFFFAOYSA-N 0.000 description 2
- WGTYBPLFGIVFAS-UHFFFAOYSA-M tetramethylammonium hydroxide Chemical compound [OH-].C[N+](C)(C)C WGTYBPLFGIVFAS-UHFFFAOYSA-M 0.000 description 2
- 229910021642 ultra pure water Inorganic materials 0.000 description 2
- 239000012498 ultrapure water Substances 0.000 description 2
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 125000000217 alkyl group Chemical group 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 125000004432 carbon atom Chemical group C* 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- 238000004031 devitrification Methods 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 239000002612 dispersion medium Substances 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000000635 electron micrograph Methods 0.000 description 1
- 238000001879 gelation Methods 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000005342 ion exchange Methods 0.000 description 1
- 238000007561 laser diffraction method Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 238000000206 photolithography Methods 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 239000005373 porous glass Substances 0.000 description 1
- 235000019353 potassium silicate Nutrition 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 238000000790 scattering method Methods 0.000 description 1
- 150000004760 silicates Chemical class 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 238000003980 solgel method Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000003892 spreading Methods 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
Images
Landscapes
- Optical Elements Other Than Lenses (AREA)
- Silicon Compounds (AREA)
Description
本発明は、光拡散部材や、真空チャックにおける被吸着材に好適なシリカ多孔体に関する。 TECHNICAL FIELD The present invention relates to a porous silica material suitable for a light diffusing member and a material to be adsorbed in a vacuum chuck.
半導体デバイスの高集積化には集積回路の微細化が必要であることから、フォトリソグラフィ等を用いた微細加工技術に対して要求が高まっている。
このため、紫外線などを均一に照射する光拡散版や半導体ウェーハを保持する真空チャックなどにも光の均一性や変形しない強度等の特性が求められている。
2. Description of the Related Art Since miniaturization of integrated circuits is necessary for high integration of semiconductor devices, there is an increasing demand for microfabrication techniques using photolithography and the like.
For this reason, characteristics such as uniformity of light and strength against deformation are required for a light diffusion plate that uniformly irradiates ultraviolet rays and the like and a vacuum chuck that holds a semiconductor wafer.
このようなシリカガラス基板としては、光透過性の基材中に、基材と屈折率の異なる微細な粒子や気泡などを存在させた複合材が用いられている。例えば、特許文献１では、緻密質シリカガラスと、この表面に形成された多孔質シリカガラスとからなる複合シリカガラス製光拡散部材として、該多孔質シリカガラスが、球状シリカガラスからなり、かつその間隙に連通気孔部を形成した多孔体であり、該緻密質シリカガラスとの界面から外表面まで均質な気孔分布を有するシリカガラスが開示されている。特許文献１では、平均粒径７５μｍの球状シリカ粒子とシリカゾルとを混合し、ゲル化させた後、焼成することで緻密質シリカガラスと多孔質ガラスとを複合化させており、緻密質シリカガラスは、光拡散部材の支持体としての強度を保持している。 As such a silica glass substrate, a composite material is used in which fine particles or air bubbles having a refractive index different from that of the base material are present in the light-transmitting base material. For example, in Patent Document 1, as a composite silica glass light diffusing member comprising dense silica glass and porous silica glass formed on the surface thereof, the porous silica glass is made of spherical silica glass, and A silica glass is disclosed which is a porous body with continuous pores formed in the gaps and has a uniform pore distribution from the interface with the dense silica glass to the outer surface. In Patent Document 1, spherical silica particles having an average particle diameter of 75 μm and silica sol are mixed, gelled, and then fired to form a composite of dense silica glass and porous glass. maintains strength as a support for the light diffusing member.
基材と屈折率の異なる微細な粒子とを混在させた光拡散部材においては、粒子の屈折率、粒子形状または濃度によって光拡散の程度を変えられるものの、紫外線の透過率は低い。 In a light diffusion member in which a base material and fine particles having different refractive indices are mixed, the degree of light diffusion can be changed by the refractive index, particle shape or concentration of the particles, but the transmittance of ultraviolet rays is low.
また、これらのシリカガラスを例えば、光拡散部材に用いる場合、支持体となるシリカガラスが複合化のための熱処理により、失透したり変形するなどの課題があった。一方、真空チャックのワーク吸着面に使用する場合、ワーク固定のため、表面の平面度の精度が必要となるが、多孔質ガラスの強度が低いため、加工精度が低いという課題もあった。 Further, when these silica glasses are used for light diffusion members, for example, there is a problem that the silica glass serving as a support is devitrified or deformed by heat treatment for compositing. On the other hand, when it is used as the workpiece adsorption surface of a vacuum chuck, the accuracy of surface flatness is required to fix the workpiece.
一方、特許文献２では、アルコキシシランを出発原料としてゾルゲル法により製造されたシリカゲルのみを用いて、透明な（緻密な）シリカからなる拡散炉やシリコン単結晶引き上げ用ルツボを製造することが示されているが、多孔体を高強度化する技術は示されていない。 On the other hand, Patent Document 2 discloses that a diffusion furnace made of transparent (dense) silica and a crucible for pulling a silicon single crystal are manufactured using only silica gel manufactured by a sol-gel method using alkoxysilane as a starting material. However, no technique for increasing the strength of the porous body is disclosed.
本発明は、支持体石英ガラスを必要とせず、光拡散部材や真空チャックなどの用途に好適な、高強度でかつ、加温による失透または変形、あるいは照度斑が生じないシリカ多孔体の製造方法を提供することを目的とする。 INDUSTRIAL APPLICABILITY The present invention does not require quartz glass as a support, and is suitable for applications such as light diffusion members and vacuum chucks. The purpose is to provide a method.
本発明は、上記した従来技術における課題を解決するものであり、以下の事項からなる。
本発明のシリカ多孔体は、平均粒径３０μｍ以上１００μｍ以下のシリカ粒子と、ＴＥＯＳをシリカ源とするシリカゾルと、シリカゾルをゲル化し粉砕した粒径１０μｍ以下のシリカゲルの微粉とを混合し、得られた混合物をゲル化し、焼成するシリカ多孔体の製造方法であって、シリカ粒子とシリカゾル中のＴＥＯＳとシリカゲルとの重量比が、シリカ粒子：シリカゾル中のＴＥＯＳ：シリカゲル＝１０：１～３：０．５～１．５であることを特徴とする。
前記シリカ粒子は、球状粒子からなることが好ましい。
The present invention is intended to solve the above-described problems in the prior art, and consists of the following matters.
The porous silica of the present invention is obtained by mixing silica particles having an average particle size of 30 μm or more and 100 μm or less, silica sol using TEOS as a silica source, and silica gel fine powder having a particle size of 10 μm or less obtained by gelling and pulverizing the silica sol. A method for producing a silica porous body by gelling and calcining a mixture, wherein the weight ratio of silica particles to TEOS in the silica sol and silica gel is 10:1 to 3:0. .5 to 1.5 .
The silica particles are preferably spherical particles.
本発明によれば、シリカゾルをゲル化し粉砕した微粉を添加することにより、シリカ多孔体を高強度化できるため、該シリカ多孔体を用いる際に、ハンドリングで破損する可能性が低くなる。シリカ多孔体の強度が増すことで、加工精度が上がり平面度が向上する。また、シリカ多孔体を支持する緻密体を必要としない。
本発明に係るシリカ多孔体は、従来技術のシリカガラスより約２％高い紫外線光透過率を有する。そのため、シリカ多孔体を厚みを出して使用することができ、強度を上げることができる。
本発明に係るシリカ多孔体は、ガス透過性に優れ、また良好な光透過率を示すことから、光拡散性にも優れる。よって、光拡散部材や真空チャックにおけるワーク吸着面の吸着部材として好適に用いられる。
According to the present invention, the silica porous body can be strengthened by adding fine powder obtained by gelling and pulverizing silica sol, so that the porous silica body is less likely to be damaged during handling when used. By increasing the strength of the silica porous body, the processing accuracy is increased and the flatness is improved. Moreover, no dense body is required to support the silica porous body.
The porous silica according to the present invention has an ultraviolet light transmittance about 2% higher than silica glass of the prior art. Therefore, the silica porous body can be used with a greater thickness, and the strength can be increased.
The porous silica according to the present invention is excellent in gas permeability and exhibits good light transmittance, and thus is also excellent in light diffusion. Therefore, it can be suitably used as a light diffusing member or a chucking member for a workpiece chucking surface in a vacuum chuck.
本発明に係るシリカ多孔体は、平均粒径３０μｍ以上１００μｍ以下のシリカ粒子と、シリカゾルとを混合し、得られた混合物をゲル化焼成することにより製造され、前記シリカ粒子とシリカゾルとの混合に際して、シリカゾルをゲル化し、粉砕した微粉を添加することにより製造することを特徴とする。 The porous silica material according to the present invention is produced by mixing silica particles having an average particle size of 30 μm or more and 100 μm or less and silica sol, and gelling and firing the resulting mixture. , characterized in that it is produced by gelling silica sol and adding pulverized fine powder.
シリカ粒子の平均粒径は３０μｍ以上１００μｍ以下、好ましくは５０μｍ以上８０μｍ以下である。平均粒径が３０μｍ未満では、２５０～８００ｎｍの波長範囲において光の透過率が充分でなく、また、シリカ粒子の平均粒径が３０μｍ未満では、３０μｍ未満の粒子径のものを多量に含む原料シリカ粒子を用いることになり、焼結時の収縮率が高く、応力集中が生じ、シリカ多孔体が反りやクラックを有するものとなり、光拡散部材や真空チャックへの適用に支障が生じることがある。一方、平均粒径が１００μｍを超えると、紫外線等の拡散性が不充分となり、また、得られるシリカ多孔体が強度不足となり、粒子の脱落が生じるなどの不具合が生じることがある。さらに、シリカガラスの粒径の最小値は１０μｍであり、最大値は２５０μｍであり、この範囲内に粒径分布のピーク値を１つ有することがより好ましい。これにより、紫外線透過の面内均一性が得られ、安定した拡散光を実現することができる。 The silica particles have an average particle diameter of 30 μm or more and 100 μm or less, preferably 50 μm or more and 80 μm or less. If the average particle size is less than 30 μm, the light transmittance is not sufficient in the wavelength range of 250 to 800 nm, and if the average particle size of the silica particles is less than 30 μm, the raw silica contains a large amount of particles having a particle size of less than 30 μm. Since particles are used, the shrinkage rate during sintering is high, stress concentration occurs, and the silica porous body has warpage and cracks, which may hinder its application to light diffusion members and vacuum chucks. On the other hand, if the average particle diameter exceeds 100 μm, the diffusibility of ultraviolet rays and the like becomes insufficient, and the strength of the resulting silica porous body becomes insufficient, which may cause problems such as the particles falling off. Furthermore, the minimum value of the particle size of silica glass is 10 μm and the maximum value is 250 μm, and it is more preferable to have one peak value of the particle size distribution within this range. As a result, in-plane uniformity of ultraviolet transmission can be obtained, and stable diffused light can be realized.
前記シリカ粒子は、球状であることが好ましい。球状シリカ粒子は、真球度および平滑性に優れたガラス微粒子である。
なお、球状シリカ粒子の球状とは、真球度が０．９以上１以下のシリカ粉が全体の９０％以上を占める群のことを言う。本発明において、真球度とは、ひとつのシリカ粉における最大直径に対する最小直径の比によって表され、真球度の値は、シリカ粉の電子顕微鏡写真において、ランダムに２０個の粉を選んで、それぞれの最大直径と最小直径を測定して算定したものである。また、平均粒径は、レーザ回折・散乱法により測定する。
The silica particles are preferably spherical. Spherical silica particles are fine glass particles with excellent sphericity and smoothness.
In addition, the spherical shape of the spherical silica particles refers to a group in which silica powder having a sphericity of 0.9 or more and 1 or less accounts for 90% or more of the whole. In the present invention, sphericity is represented by the ratio of the minimum diameter to the maximum diameter in one silica powder, and the sphericity value is obtained by randomly selecting 20 powders in an electron micrograph of silica powder. , calculated by measuring the respective maximum and minimum diameters. Also, the average particle size is measured by a laser diffraction/scattering method.
上記球状シリカ粒子は、中実で透明なガラス構造体であることが好ましい。これにより、紫外線の透過率をより高く、かつ、より均一化することができる。 The spherical silica particles are preferably solid and transparent glass structures. Thereby, the transmittance of ultraviolet rays can be made higher and more uniform.
また、本発明に係るシリカ多孔体では、その骨格をなす球状シリカ粒子の間隙に連通気孔部が形成され、該連通気孔部の中心気孔径は１０μｍ以上２０μｍ以下であることが好ましい。なお、気孔径は、ＪＩＳＲ １６３４に基づき水銀圧入法により測定する。前記中心気孔径の大きさは、前記球状シリカ粒子の平均粒径の２０％±５％であることがより最適である。これによって、光源からの紫外線の出射効率をより高めることができ、また出射される紫外線の拡散性をより高めることができる。 Further, in the porous silica material according to the present invention, it is preferable that communicating pores are formed between the spherical silica particles forming the skeleton thereof, and the central pore diameter of the communicating pores is 10 μm or more and 20 μm or less. The pore diameter is measured by mercury intrusion method based on JISR 1634. More optimally, the size of the central pore size is 20%±5% of the average particle size of the spherical silica particles. As a result, the output efficiency of ultraviolet rays from the light source can be further increased, and the diffusivity of the emitted ultraviolet rays can be further increased.
シリカゾルは、一般に７ｎｍ以上１５０ｎｍ以下の粒径を持つシリカ粒子が水または有機溶媒に分散した状態にあるものをいい、典型的には水を分散媒とした水性シリカゾルである。
シリカゾルの原料は、ケイ酸ナトリウムで、その成分はＳｉＯ2、Ｎａ2Ｏおよび水である。シリカゾルは、水ガラスと呼ばれるケイ酸ナトリウムの濃い水溶液を用いて、中和またはイオン交換により得られる。また、シリカゾルの調製方法には、塩基性溶媒を含むアルコール水溶液中でケイ素アルコキシドを加水分解する方法や、ケイ素アルコキシドを有機塩基化合物で加水分解する方法もある。ケイ素アルコキシドには、例えば、テトラメチルシリケート（ＴＭＯＳ）、テトラエチルシリケート（ＴＥＯＳ）、メチルトリエチルシリケート、ジメチルジエチルシリケート、トリメチルエチルシリケート、および炭素原子数１～２のアルキル基のトリアルキルシリケートなどが用いられる。有機塩基化合物には、例えば、アンモニアや水酸化テトラメチルアンモニウムなどが用いられる。
Silica sol generally refers to a state in which silica particles having a particle size of 7 nm or more and 150 nm or less are dispersed in water or an organic solvent, and is typically an aqueous silica sol using water as a dispersion medium.
The raw material of silica sol is sodium silicate, and its components are SiO 2 , Na 2 O and water. Silica sols are obtained by neutralization or ion exchange using concentrated aqueous solutions of sodium silicate called water glass. In addition, methods for preparing silica sol include a method of hydrolyzing a silicon alkoxide in an aqueous alcohol solution containing a basic solvent, and a method of hydrolyzing a silicon alkoxide with an organic base compound. Silicon alkoxides include, for example, tetramethyl silicate (TMOS), tetraethyl silicate (TEOS), methyltriethyl silicate, dimethyldiethyl silicate, trimethylethyl silicate, trialkyl silicates of alkyl groups having 1 to 2 carbon atoms, and the like. . Examples of the organic base compound include ammonia and tetramethylammonium hydroxide.
その他、コロイダルシリカ粒子を含むシリカゾル分散液にアンモニアなどのアミン化合物を添加して、ｐＨを制御しながら濃縮してシリカゾルを製造する方法もある。この場合、コロイダルシリカ粒子には、窒素吸着法による比表面積が２０～５００ｍ2／ｇで、かつ、表面積当たりの吸湿量が０．５ｍｇ／ｍ2であるものを用いる。
本発明に係るシリカゾルは、上記したいずれの方法でも調製することができる。
In addition, there is also a method of adding an amine compound such as ammonia to a silica sol dispersion containing colloidal silica particles and concentrating the mixture while controlling the pH to produce a silica sol. In this case, the colloidal silica particles to be used have a specific surface area of 20 to 500 m 2 /g as determined by the nitrogen adsorption method and a moisture absorption amount per surface area of 0.5 mg/m 2 .
The silica sol according to the present invention can be prepared by any of the methods described above.
本発明に係るシリカ多孔体は、シリカ粒子およびシリカゾルを混合した後、該混合物中に、シリカゾルをゲル化し粉砕した微粉を添加し、ゲル化し、焼成することにより得られる。
シリカゾルに添加されるシリカゲルは、粒径が１０μｍ以下のものが好ましく、その形状は破砕状でかまわない。このようなゲルを添加することで、シリカ粒子同士の接触部に微細なシリカが集中し、いわゆるネックを形成して強度を向上させることができる。また、その添加量は、シリカ粒子の重量の５％以上１５％以下であることが好ましい。５％未満では強度が向上せず、１５％を超えると、気孔を塞ぎガス透過性が充分でなくなる。なお、シリカゲル粒子の粒径を１０μｍ以下としたが、その粒径の測定方法は、ＳＥＭ観察による。
The porous silica material according to the present invention is obtained by mixing silica particles and silica sol, then adding fine powder obtained by gelling and pulverizing silica sol to the mixture, gelling and firing.
The silica gel added to the silica sol preferably has a particle size of 10 μm or less, and may be crushed. By adding such a gel, fine silica concentrates at the contact portion between silica particles, forming a so-called neck and improving the strength. Moreover, the amount of addition is preferably 5% or more and 15% or less of the weight of the silica particles. If it is less than 5%, the strength is not improved, and if it exceeds 15%, the pores are closed and the gas permeability becomes insufficient. The particle size of the silica gel particles was set to 10 μm or less, and the particle size was measured by SEM observation.
ここで、シリカゾルをゲル化し粉砕した微粉について説明する。テトラエトキシシラン（ＴＥＯＳ）などを加水分解して生成したシリカゾルは、時間の経過とともに脱水縮合して三次元ネットワークを形成する。
前記シリカゲルを乾燥させた後、最大粒径が３０μｍ以下の大きさ、好ましくは１０μｍ以下に粉砕する。粉砕は、ボールミルまたは乳鉢などを用いて行う。 After drying the silica gel, it is pulverized to a maximum particle size of 30 μm or less, preferably 10 μm or less. Pulverization is performed using a ball mill, mortar, or the like.
前記シリカ多孔体の製造方法では、シリカ粒子およびシリカゾルの混合物に、このようなシリカゲルの微粉を添加することで、ゲル化焼成の進行中に、ゾルゲル部分が先に軟化しシリカ粒子のネックとなる。シリカゾルだけでなくシリカゲルの微粉を添加することでネック部のシリカの量が増し、得られるシリカ多孔体の強度を向上させることができる。シリカ多孔体のＳＥＭ（走査型電子顕微鏡）で観察すると、その粒子同士をつなぐネックが太くなっていることがわかる。そのため強度が増し、研削加工による粒子剥がれが少なく、より多くの粒子自体が削られていることがわかり、加工による精度向上にも期待ができる。 In the method for producing a silica porous body, by adding such silica gel fine powder to a mixture of silica particles and silica sol, the sol-gel portion softens first and becomes a neck of the silica particles during the gelation firing. . By adding fine powder of silica gel as well as silica sol, the amount of silica in the neck portion is increased, and the strength of the resulting porous silica material can be improved. Observation of the silica porous material with an SEM (scanning electron microscope) reveals that the necks connecting the particles are thickened. As a result, the strength increases, there is less peeling of particles due to grinding, and it can be seen that more particles themselves are scraped off, which can be expected to improve accuracy through processing.
なお、シリカ粒子、シリカゾル、およびシリカゲルの配合割合は、前記シリカゾルがＴＥＯＳをシリカ源とするものである場合は、重量比が、シリカ粒子：シリカゾル中のＴＥＯＳ：シリカゲル＝１０：１～３：０．５～１．５であることが好ましい。ＴＥＯＳがこの範囲を超えると適当な形状と気孔を維持しづらくなる。シリカゲルが０．５を下回ると強度は向上せず、１．５を上回れば光の透過性が悪くなる。 When the silica sol uses TEOS as a silica source, the weight ratio of the silica particles, the silica sol, and the silica gel is silica particles:TEOS:silica gel in the silica sol=10:1 to 3:0. It is preferably between 0.5 and 1.5. If TEOS exceeds this range, it becomes difficult to maintain proper shape and pores. If the silica gel is less than 0.5, the strength is not improved, and if it exceeds 1.5, the light transmittance is deteriorated.
本発明に係るシリカ多孔体は、ＪＩＳＲ１６０１に準拠した３点曲げ強度が１０．５～１１．３ＭＰａと、高強度であるため、加工精度に優れ、例えば、真空チャックのワーク吸着面の被吸着部材に用いた場合、平面度の高い吸着面を形成することができる。また、光透過率も波長５００～８００ｎｍで２０．０～２０．７％と良好である。よって、光拡散部材として用いる場合、高強度化のためにシリカ多孔体を複合化する必要がないため、複合化に伴う失透や変形、または照度斑を生じることがなく、好適である。 The porous silica material according to the present invention has a three-point bending strength of 10.5 to 11.3 MPa in accordance with JISR1601, which is high strength, and therefore has excellent processing accuracy. , it is possible to form an attraction surface with high flatness. Also, the light transmittance is good at 20.0 to 20.7% at a wavelength of 500 to 800 nm. Therefore, when it is used as a light diffusing member, it is not necessary to compound the silica porous material for increasing the strength, and thus devitrification, deformation, or illuminance spots due to compounding do not occur, which is suitable.
以下、本発明を実施例に基づいて具体的に説明するが、本発明は、下記実施例により制限されるものではない。
［実施例１］
オルトケイ酸テトラエチル（ＴＥＯＳ）、超純水、０．１ｍｏｌ／Ｌ 塩酸、およびプロピレングリコールを、ＴＥＯＳ：超純水：塩酸：プロピレングリコール＝１１．７：９：１：３の重量比で混合し、スターラーで攪拌した後、０．１ｍｏｌ／Ｌアンモニア水を、前記の重量比に対しておよそ１．３添加し、ｐＨ４．５～５．０に調整し、シリカゾルを得た。
得られたシリカゾルを室温で一晩放置してゲル化させ、その後、１２０℃で３日間乾燥させた後、粉砕した。さらに粉砕物を６００℃で２時間熱処理し、得られたシリカゲルを乳鉢にて粉砕した。
このシリカゲルと、前記の方法で新たに調製したシリカゾルと、平均粒径が７５μｍの球状シリカ粒子とを１：５：１０の重量比で混合し、φ３０×１０の塩化ビニル製の型内に入れて鋳込み、室温で１２時間放置してゲル化させた後、１３７０℃で１２時間保持することでシリカ多孔体１を得た。
ＳＥＭ像から、シリカ多孔体１は、球状シリカ粒子が球状を保持しており、粒子が均一に分散していることがわかった。
EXAMPLES The present invention will be specifically described below based on examples, but the present invention is not limited to the following examples.
[Example 1]
Tetraethyl orthosilicate (TEOS), ultrapure water, 0.1 mol/L hydrochloric acid, and propylene glycol were mixed at a weight ratio of TEOS: ultrapure water: hydrochloric acid: propylene glycol = 11.7:9:1:3. After stirring with a stirrer, about 1.3 of 0.1 mol/L aqueous ammonia was added to the above weight ratio to adjust the pH to 4.5 to 5.0 to obtain silica sol.
The resulting silica sol was allowed to stand overnight at room temperature to gel, dried at 120° C. for 3 days, and then pulverized. Further, the pulverized product was heat-treated at 600° C. for 2 hours, and the obtained silica gel was pulverized in a mortar.
This silica gel, silica sol newly prepared by the above method, and spherical silica particles with an average particle size of 75 μm were mixed at a weight ratio of 1:5:10, and placed in a vinyl chloride mold of φ30×10. The silica porous body 1 was obtained by casting at room temperature for 12 hours to gel and then holding at 1370° C. for 12 hours.
From the SEM image, it was found that the spherical silica particles of the silica porous body 1 retained their spherical shape, and the particles were uniformly dispersed.
［比較例１］
実施例１と同じ方法で調製したシリカゾルと、平均粒径が７５μｍの球状シリカ粒子とを５：１２の重量比で混合し、実施例１と同様にして鋳込み、ゲル化させた後、１３７０℃で１２時間保持することでシリカ多孔体２を得た。
ＳＥＭ像から、シリカ多孔体２は、球状シリカ粒子が互いに融着し、球状を充分に保持しておらず、凝集した状態であった。
[Comparative Example 1]
Silica sol prepared by the same method as in Example 1 and spherical silica particles with an average particle diameter of 75 μm were mixed at a weight ratio of 5:12, cast and gelled in the same manner as in Example 1, and then heated to 1370°C. The silica porous body 2 was obtained by hold|maintaining at 12 hours.
From the SEM image, the silica porous body 2 was found to be in an agglomerated state in which the spherical silica particles were fused to each other and the spherical shape was not sufficiently maintained.
◆３点曲げ強度
ＪＩＳＲ１６０１に準拠した３点曲げ試験を行った。
シリカ多孔体を長さ４０ｍｍ、幅４ｍｍ、および厚さ３ｍｍの大きさに裁断し、試験片を作製した。試験片は、一種類につき、５～１０個用意し、強度の平均値を求めた。
図３に示すように、シリカ多孔体１の強度がシリカ多孔体２よりも２０％以上向上することがわかった。
◆Three-point bending strength A three-point bending test was conducted in accordance with JISR1601.
A silica porous body was cut into a size of 40 mm in length, 4 mm in width, and 3 mm in thickness to prepare a test piece. Five to ten test pieces were prepared for each type, and the average value of strength was obtained.
As shown in FIG. 3, it was found that the strength of the silica porous body 1 was improved by 20% or more compared to that of the silica porous body 2.
◆透過率（□３０×ｔ１ｍｍ）
シリカガラス多孔体を３０ｍｍ四方および厚さ１ｍｍの大きさに裁断し、試験片を作製した。光学透過率測定器ＵＶ－２４５０（（株）島津製作所製）を用いて、測定波長２５０～８００ｎｍで透過率を測定した。
図４に示すように、多孔体１の透過率が多孔体２の透過率より２％向上した。
◆Transmittance (□30×t1mm)
A silica glass porous body was cut into a size of 30 mm square and 1 mm thick to prepare a test piece. Transmittance was measured at a measurement wavelength of 250 to 800 nm using an optical transmittance meter UV-2450 (manufactured by Shimadzu Corporation).
As shown in FIG. 4, the transmittance of porous body 1 was improved by 2% from the transmittance of porous body 2 .
本発明に係るシリカ多孔体は、レーザ等の光を広げるための光拡散部材や、真空チャックのワーク吸着面に用いる被吸着部材として好適に用いられる。 INDUSTRIAL APPLICABILITY The silica porous body according to the present invention is suitably used as a light diffusing member for spreading light of a laser or the like, or as a member to be adsorbed for use as a workpiece adsorption surface of a vacuum chuck.
Claims (2)
シリカ粒子とシリカゾル中のＴＥＯＳとシリカゲルとの重量比が、シリカ粒子：シリカゾル中のＴＥＯＳ：シリカゲル＝１０：１～３：０．５～１．５であることを特徴とするシリカ多孔体の製造方法。 Silica particles having an average particle size of 30 μm or more and 100 μm or less, silica sol using TEOS as a silica source, and fine powder of silica gel having a particle size of 10 μm or less obtained by gelling and pulverizing the silica sol are mixed, and the obtained mixture is gelled and fired. A method for producing a silica porous body,
Manufacture of a porous silica material characterized in that the weight ratio of silica particles to TEOS in silica sol and silica gel is silica particles: TEOS in silica sol: silica gel = 10: 1 to 3: 0.5 to 1.5 Method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2018217628A JP7130529B2 (en) | 2018-11-20 | 2018-11-20 | Method for producing porous silica |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2018217628A JP7130529B2 (en) | 2018-11-20 | 2018-11-20 | Method for producing porous silica |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2020083682A JP2020083682A (en) | 2020-06-04 |
| JP7130529B2 true JP7130529B2 (en) | 2022-09-05 |
Family
ID=70909586
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2018217628A Active JP7130529B2 (en) | 2018-11-20 | 2018-11-20 | Method for producing porous silica |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP7130529B2 (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2018123233A (en) | 2017-01-31 | 2018-08-09 | 日東電工株式会社 | Void layer, void layer-containing adhesive sheet, method for producing void layer, method for producing void layer-containing adhesive sheet, and optical device |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05345685A (en) * | 1992-06-15 | 1993-12-27 | Toshiba Ceramics Co Ltd | Production of siliceous porous material |
-
2018
- 2018-11-20 JP JP2018217628A patent/JP7130529B2/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2018123233A (en) | 2017-01-31 | 2018-08-09 | 日東電工株式会社 | Void layer, void layer-containing adhesive sheet, method for producing void layer, method for producing void layer-containing adhesive sheet, and optical device |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2020083682A (en) | 2020-06-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5084670B2 (en) | Silica sol and method for producing the same | |
| JP2009018960A (en) | Production and use of polysilicate particulate material | |
| JP2002338232A (en) | Secondary flocculated colloidal silica, method for producing the same and abrasive composition using the same | |
| GB2329893A (en) | Sol-gel method of manufacturing a silica glass article from silica with two particle sizes | |
| TW202134179A (en) | Silica particles, silica sol, polishing composition, polishing method, method for manufacturing semiconductor wafer, and method for manufacturing semiconductor device | |
| JP6355077B2 (en) | Method for producing coating liquid for porous mesoporous silica membrane and method for producing porous mesoporous silica membrane | |
| JP7130529B2 (en) | Method for producing porous silica | |
| JP2007061989A (en) | Polishing composite-oxide particle and slurry abrasive | |
| JPH07206451A (en) | Production of synthetic quartz glass | |
| TWI780292B (en) | Opaque quartz glass and method of making the same | |
| TW202035316A (en) | Opaque quartz glass and production method therefor | |
| JP2018090440A (en) | Method for manufacturing optical component having acute part | |
| TWI616341B (en) | Method for producing a composite body of a material with a high silicic acid content | |
| JP2020083674A (en) | Transparent silica glass composition, transparent silica glass and method for manufacturing the same | |
| JP7331437B2 (en) | Silica particles, silica sol, polishing composition, polishing method, semiconductor wafer manufacturing method, and semiconductor device manufacturing method | |
| Nakamura et al. | A novel route to luminescent opals for controlling spontaneous emission | |
| JP6707409B2 (en) | Silica sintered body | |
| JP6782088B2 (en) | A coating liquid for forming a film and a base material with a coating using the coating liquid. | |
| CA2398876A1 (en) | Sol-gel process for producing synthetic silica glass | |
| JP2010241642A (en) | Colloidal silica | |
| JP7331436B2 (en) | Silica particles, silica sol, polishing composition, polishing method, semiconductor wafer manufacturing method, and semiconductor device manufacturing method | |
| JP7331435B2 (en) | Silica particles, silica sol, polishing composition, polishing method, semiconductor wafer manufacturing method, and semiconductor device manufacturing method | |
| JP7565671B2 (en) | Method for producing silica sol and method for suppressing intermediate products in silica sol | |
| WO2022071020A1 (en) | Boron-containing silica dispersion, and method for producing same | |
| JP5356209B2 (en) | Organic solvent dispersed high concentration silicic acid solution |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20181225 |
|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20210607 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20220324 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20220419 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20220511 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20220823 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20220824 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 7130529 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| S533 | Written request for registration of change of name |
Free format text: JAPANESE INTERMEDIATE CODE: R313533 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |