JPH0343202B2 - - Google Patents
Info
- Publication number
- JPH0343202B2 JPH0343202B2 JP61012658A JP1265886A JPH0343202B2 JP H0343202 B2 JPH0343202 B2 JP H0343202B2 JP 61012658 A JP61012658 A JP 61012658A JP 1265886 A JP1265886 A JP 1265886A JP H0343202 B2 JPH0343202 B2 JP H0343202B2
- Authority
- JP
- Japan
- Prior art keywords
- particle size
- average particle
- oxide
- particles
- powder
- 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.)
- Expired - Lifetime
Links
- 239000002245 particle Substances 0.000 claims description 87
- 239000007788 liquid Substances 0.000 claims description 45
- 239000000843 powder Substances 0.000 claims description 24
- 238000000034 method Methods 0.000 claims description 19
- 238000001035 drying Methods 0.000 claims description 18
- 239000000084 colloidal system Substances 0.000 claims description 17
- 229910052809 inorganic oxide Inorganic materials 0.000 claims description 10
- 238000005507 spraying Methods 0.000 claims description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 6
- 239000011148 porous material Substances 0.000 claims description 6
- 239000011164 primary particle Substances 0.000 claims description 5
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims description 3
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 3
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 claims description 3
- 229910052782 aluminium Inorganic materials 0.000 claims description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 3
- 229910052787 antimony Inorganic materials 0.000 claims description 3
- WATWJIUSRGPENY-UHFFFAOYSA-N antimony atom Chemical compound [Sb] WATWJIUSRGPENY-UHFFFAOYSA-N 0.000 claims description 3
- 229910052742 iron Inorganic materials 0.000 claims description 3
- 229910052718 tin Inorganic materials 0.000 claims description 3
- 239000010936 titanium Substances 0.000 claims description 3
- 229910052719 titanium Inorganic materials 0.000 claims description 3
- 229910052726 zirconium Inorganic materials 0.000 claims description 3
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 2
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 2
- 229910052749 magnesium Inorganic materials 0.000 claims description 2
- 239000011777 magnesium Substances 0.000 claims description 2
- 229910052710 silicon Inorganic materials 0.000 claims description 2
- 239000010703 silicon Substances 0.000 claims description 2
- 229910052725 zinc Inorganic materials 0.000 claims description 2
- 239000011701 zinc Substances 0.000 claims description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 34
- 239000000377 silicon dioxide Substances 0.000 description 17
- 239000007787 solid Substances 0.000 description 9
- 239000000243 solution Substances 0.000 description 9
- 238000001694 spray drying Methods 0.000 description 8
- 239000012530 fluid Substances 0.000 description 5
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 4
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 4
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 4
- QGZKDVFQNNGYKY-UHFFFAOYSA-N ammonia Natural products N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 4
- ADCOVFLJGNWWNZ-UHFFFAOYSA-N antimony trioxide Chemical compound O=[Sb]O[Sb]=O ADCOVFLJGNWWNZ-UHFFFAOYSA-N 0.000 description 4
- 239000002612 dispersion medium Substances 0.000 description 4
- 230000003301 hydrolyzing effect Effects 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- 239000002244 precipitate Substances 0.000 description 4
- 239000002994 raw material Substances 0.000 description 4
- 239000012798 spherical particle Substances 0.000 description 4
- 239000007921 spray Substances 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 239000006185 dispersion Substances 0.000 description 3
- 238000000635 electron micrograph Methods 0.000 description 3
- 238000010438 heat treatment 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
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- BOTDANWDWHJENH-UHFFFAOYSA-N Tetraethyl orthosilicate Chemical compound CCO[Si](OCC)(OCC)OCC BOTDANWDWHJENH-UHFFFAOYSA-N 0.000 description 2
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 description 2
- 239000003153 chemical reaction reagent Substances 0.000 description 2
- 238000001246 colloidal dispersion Methods 0.000 description 2
- 235000019441 ethanol Nutrition 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 230000003472 neutralizing effect Effects 0.000 description 2
- 235000019353 potassium silicate Nutrition 0.000 description 2
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 description 2
- 235000012239 silicon dioxide Nutrition 0.000 description 2
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 2
- NWUYHJFMYQTDRP-UHFFFAOYSA-N 1,2-bis(ethenyl)benzene;1-ethenyl-2-ethylbenzene;styrene Chemical compound C=CC1=CC=CC=C1.CCC1=CC=CC=C1C=C.C=CC1=CC=CC=C1C=C NWUYHJFMYQTDRP-UHFFFAOYSA-N 0.000 description 1
- 229910021578 Iron(III) chloride Inorganic materials 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- 239000004115 Sodium Silicate Substances 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 229910052910 alkali metal silicate Inorganic materials 0.000 description 1
- 125000003277 amino group Chemical group 0.000 description 1
- 229910000410 antimony oxide Inorganic materials 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000002537 cosmetic Substances 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000007865 diluting Methods 0.000 description 1
- TVQLLNFANZSCGY-UHFFFAOYSA-N disodium;dioxido(oxo)tin Chemical compound [Na+].[Na+].[O-][Sn]([O-])=O TVQLLNFANZSCGY-UHFFFAOYSA-N 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000001493 electron microscopy Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 235000013305 food Nutrition 0.000 description 1
- 150000003840 hydrochlorides Chemical class 0.000 description 1
- 238000003703 image analysis method Methods 0.000 description 1
- 239000003456 ion exchange resin Substances 0.000 description 1
- 229920003303 ion-exchange polymer Polymers 0.000 description 1
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000011859 microparticle Substances 0.000 description 1
- 150000002823 nitrates Chemical class 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- VTRUBDSFZJNXHI-UHFFFAOYSA-N oxoantimony Chemical compound [Sb]=O VTRUBDSFZJNXHI-UHFFFAOYSA-N 0.000 description 1
- RVTZCBVAJQQJTK-UHFFFAOYSA-N oxygen(2-);zirconium(4+) Chemical compound [O-2].[O-2].[Zr+4] RVTZCBVAJQQJTK-UHFFFAOYSA-N 0.000 description 1
- 239000004597 plastic additive Substances 0.000 description 1
- 235000011121 sodium hydroxide Nutrition 0.000 description 1
- 229910052911 sodium silicate Inorganic materials 0.000 description 1
- 229940079864 sodium stannate Drugs 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- 239000000271 synthetic detergent Substances 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
- 239000011135 tin Substances 0.000 description 1
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 description 1
- 229910001887 tin oxide Inorganic materials 0.000 description 1
- HPGGPRDJHPYFRM-UHFFFAOYSA-J tin(iv) chloride Chemical compound Cl[Sn](Cl)(Cl)Cl HPGGPRDJHPYFRM-UHFFFAOYSA-J 0.000 description 1
- 229910001928 zirconium oxide Inorganic materials 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B13/00—Oxygen; Ozone; Oxides or hydroxides in general
- C01B13/14—Methods for preparing oxides or hydroxides in general
- C01B13/34—Methods for preparing oxides or hydroxides in general by oxidation or hydrolysis of sprayed or atomised solutions
Description
［産業上の利用分野］
本発明は無機酸化物又は含水酸化物からなり、
平均粒径が１〜20μの範囲にあつて、粒度分布が
シヤープな真球状粉末の製造方法に関する。
［従来の技術］
無機酸化物又は含水酸化物からなる微小粒子の
製造方法としては、無機酸化物又は含水酸化物を
含有する分散液を、加圧ノズル又は回転ノズルか
ら120〜400℃の乾燥雰囲気中に噴霧して乾燥する
方法が知られている。そして、この噴霧乾燥法は
食品、医薬品、合成洗剤、触媒、プラスチツク添
加剤などの分野でも、広く利用されている。
［発明が解決しようとする問題点］
従来の噴霧乾燥法は、乾燥雰囲気が高温であ
り、従つて噴霧液滴の乾燥速度が早いため、乾燥
粒子の形状を真球状にすることが困難である。特
に、噴霧する分散液の流動性が極端に高い場合や
固形分濃度が極端に低い場合はこの傾向が著し
い。これに加えて、従来の噴霧乾燥法では、一般
に加圧ノズル又は回転ノズルを使用している関係
で、無機酸化物又は含水無機酸化物の分散液を加
圧ノズルで噴霧する場合には、ノズル径を小さく
して高圧で噴霧しなければならず、また回転ノズ
ルで噴霧する場合には、ノズルを高速回転しなけ
ればならないが、噴霧圧や回転速度を一定の高圧
又は高速に維持することは必ずしも容易ではな
い。そして、加圧ノズルではノズルが摩耗する不
都合もある。
つまり、従来の噴霧乾燥法では微細な真球状微
粒子を歩留よく製造することができない。
本発明は無機酸化物又は含水無機酸化物を分散
質とするコロイド液を、特定な条件下に噴霧乾燥
して、平均粒径が１〜20μの範囲にあり、粒度分
布がシヤープな真球状粒子を製造する方法を提案
する。
［問題点を解決するための手段］
本発明の方法は、単一種の無機酸化物及び／又
は含水酸化物を分散質とし、その分散質の平均粒
径が2500Å以下であるコロイド液を、温度10℃〜
100℃、湿度３〜13％の範囲にある乾燥雰囲気中
に、噴霧して乾燥することを特徴とする。
［作用］
本発明に於いて、原料となるコロイド液には、
単一種の無機酸化物及び／又は含水酸化物を分散
質とし、水又は有機溶剤を分散媒とするコロイド
液がいずれも使用可能であつて、例えば、珪素、
アルミニウム、チタニウム、ジルコニウム、アン
チモン、スズ、鉄、亜鉛、マグネシウムなどから
選ばれる単一元素の酸化物及び／又は含水酸化物
を分散質とするコロイド液が使用できる。このよ
うなコロイド液は公知の任意の方法によつて調整
することができる。ちなみに、シリカコロイド液
は水ガラスなどのアルカリ珪酸塩溶液を脱アルカ
リする方法、あるいはエチルシリケートを加水分
解する方法で製造することができる。またジルコ
ニウム、チタニウム、アルミニウム、鉄などの酸
化物又は含水酸化物を分散質とするコロイド液
は、例えばこれら金属の塩酸塩、硫酸塩、硝酸塩
を加水分解するか、中和する方法で調製すること
ができ、またアンチモン、スズなどの酸化物又は
含水酸化物を分散質とするコロイド液は、三酸化
アンチモンの水分散液を過酸化水素で処理すると
か、スズ酸ソーダを適当な条件で加水分解する方
法で調製可能である。
本発明で使用される原料コロイド液を調製する
に際しては、上に例示した方法以外の方法を採用
しても差し支えない。しかし、原料コロイド液の
分散質はその平均粒径（一次粒子）が2500Å以下
であることが好ましい。コロイド液の分散質、つ
まりコロイド粒子の粒径が大きすぎると、乾燥過
程でのコロイドの粒子間強度が弱くなる関係で、
乾燥中に粒子が破壊されて粒度分布が広くなるば
かりでなく、非球状粒子の生成が増大するからで
ある。本発明で使用するコロイド液の分散粒子径
を120Å以下とした場合には、後述するような中
実球を得ることができる。
本発明によれば、原料コロイド液は、温度10℃
〜100℃、湿度３〜13％の範囲にある乾燥雰囲気
中に噴霧される。ここで言う湿度とは、乾燥雰囲
気を占める水蒸気と容量パーセントを言う。噴霧
手段としては、噴霧乾燥法で常用されている噴霧
ノズルが使用可能であるが、一般に使用されてい
る二流体ノズルを使用することが好ましい。そし
て、噴出される空気量対原料コロイド量の容量比
（以下気液比という）は10000〜500：１とするの
が適当である。
原料コロイドの液滴が乾燥される雰囲気、換言
すれば乾燥空間は、本発明の場合、温度10℃〜
100℃、湿度３〜13％の範囲に維持されなければ
ならない。乾燥雰囲気温度が上記の範囲を上廻つ
た場合には、たとえ湿度を13％と比較的高くして
も、液滴の乾燥速度が早くなりすぎ、乾燥粒子の
形状を球形にすることができない。また、乾燥温
度が上記の範囲を下廻つた場合は、液滴の乾燥が
遅く、実用的規模の乾燥空間では液滴を乾燥する
ことができない。乾燥雰囲気の湿度について言え
ば、本発明では採用する乾燥温度が比較的低いた
め、湿度を３〜13％に保持する必要がある。
ちなみに、二流体ノズルで噴霧されたコロイド
液を、上記の如き条件下にある雰囲気で乾燥すれ
ば、液滴の表面からコロイド分散媒が蒸発する速
度と、液滴内部のコロイド分散媒が表面に拡散す
る速度とが、適度にバランスするため、液滴は噴
霧されたままの形状を保持して乾燥される。そし
て、液滴は二流体ノズルによつて微細に分割され
ているので、本発明によれば、平均粒径が１〜
20μの範囲にあり、粒度分布がシヤープでしかも
真球度が0.850〜1.00である粒子を製造すること
ができる。
ここで、真球度とは噴霧乾燥して得た粒子を互
いに重ならないよう分散させ、走査型電子顕微鏡
（SEM）にて2000倍に拡大した電子顕微鏡写真を
撮り、これを島津製作所製のイメージアナライザ
ーで画像解析して粒子一個一個の投影面の面積と
円周を測定し、その面積から真円と仮定して算出
される相当直径をHD、また円周から真円と仮定
して算出される相当直径をHdとして、両者の比
を真球度とした。
真球度＝HD（面積からの相当直径）／Hd（円周か
らの相当直径）
本発明によれば、上記のように定義される真球
度が0.850〜1.00の範囲にある粒子を90％以上の
収率で得ることができ、そうした粉末を本発明で
は真球状粉末と呼ぶ。尚、当然のことながら、粒
子同志が固着したものや粒子に陥没があるもの
は、全体として真球状と認められてもその真球度
は上記の範囲外にある。
既述したように、本発明の方法では原料コロイ
ド液として、分散コロイド粒子の平均粒径が120
Å以下であるコロイド液を使用することで、嵩密
度の大きい中実球を製造することができる。そし
てコロイド粒子の平均粒径が120Å以下の範囲内
で、平均粒径が比較的大きいコロイド液と、比較
的小さいコロイド液を混合使用すれば、中実球の
嵩密度を一層高めることができる。ここで、中実
球とは細孔容積0.15ml／ｇ以下、嵩密度0.8ｇ／
ml以上の真球状粒子を言う。念のため付言する
と、本発明で得られる中実球の嵩密度は、真球を
最密充填した場合の空隙率（0.36）から算出され
る嵩密度にほぼ等しい。
［実施例］
実施例 １
珪酸ソーダ液と硫酸から調製したシリカ濃度30
％、平均粒径70Åのシリカコロイド液を、市販の
二流体ノズルの一方に５Kg／hrの流量で供給し、
他方に気体圧力を２Kg／hrの流量で供給して、コ
ロイド液を乾燥気流が流れる乾燥空間中に噴霧し
た。コロイド液が噴霧される乾燥空間の温度及び
湿度と、得られた乾燥粒子の性状を表−１に示
す。
[Industrial Application Field] The present invention consists of an inorganic oxide or a hydrous oxide,
The present invention relates to a method for producing true spherical powder having an average particle size in the range of 1 to 20 μm and a sharp particle size distribution. [Prior Art] As a method for producing microparticles made of inorganic oxides or hydrated oxides, a dispersion containing an inorganic oxide or hydrated oxide is passed through a pressure nozzle or a rotating nozzle into a dry atmosphere at 120 to 400°C. A method of spraying and drying is known. This spray drying method is also widely used in the fields of foods, pharmaceuticals, synthetic detergents, catalysts, and plastic additives. [Problems to be Solved by the Invention] In the conventional spray drying method, the drying atmosphere is at a high temperature, and therefore the drying speed of the spray droplets is fast, so it is difficult to make the dried particles into a true spherical shape. . This tendency is particularly noticeable when the fluidity of the dispersion to be sprayed is extremely high or when the solid content concentration is extremely low. In addition, in conventional spray drying methods, a pressurized nozzle or a rotating nozzle is generally used. The diameter must be small and the spray must be performed at high pressure, and when spraying with a rotating nozzle, the nozzle must be rotated at high speed, but it is not possible to maintain the spray pressure or rotation speed at a constant high pressure or high speed. It's not always easy. Moreover, the pressurized nozzle also has the disadvantage that the nozzle wears out. In other words, the conventional spray drying method cannot produce fine spherical particles with a good yield. The present invention produces true spherical particles with an average particle size in the range of 1 to 20μ and a sharp particle size distribution by spray-drying a colloidal liquid containing an inorganic oxide or a hydrous inorganic oxide as a dispersoid under specific conditions. We propose a method for manufacturing. [Means for Solving the Problems] The method of the present invention uses a single type of inorganic oxide and/or hydrous oxide as a dispersoid, and a colloidal liquid in which the average particle size of the dispersoid is 2500 Å or less is heated at a temperature 10℃～
It is characterized by being sprayed and dried in a dry atmosphere at 100°C and humidity ranging from 3 to 13%. [Function] In the present invention, the colloidal liquid serving as a raw material includes:
Any colloidal liquid containing a single type of inorganic oxide and/or hydrous oxide as a dispersoid and water or an organic solvent as a dispersion medium can be used. For example, silicon,
A colloidal liquid containing a dispersoid of an oxide and/or a hydrous oxide of a single element selected from aluminum, titanium, zirconium, antimony, tin, iron, zinc, magnesium, etc. can be used. Such a colloidal liquid can be prepared by any known method. Incidentally, the silica colloid liquid can be produced by dealkalizing an alkali silicate solution such as water glass or by hydrolyzing ethyl silicate. In addition, colloidal liquids containing oxides or hydrous oxides of zirconium, titanium, aluminum, iron, etc. as dispersoids can be prepared by, for example, hydrolyzing or neutralizing hydrochlorides, sulfates, and nitrates of these metals. In addition, colloidal liquids containing oxides or hydrous oxides such as antimony and tin as dispersants can be produced by treating an aqueous dispersion of antimony trioxide with hydrogen peroxide or by hydrolyzing sodium stannate under appropriate conditions. It can be prepared by the following method. When preparing the raw material colloidal liquid used in the present invention, methods other than those exemplified above may be employed. However, it is preferable that the average particle size (primary particles) of the dispersoid of the raw colloidal liquid is 2500 Å or less. If the dispersoid of the colloidal liquid, that is, the particle size of the colloidal particles, is too large, the interparticle strength of the colloid during the drying process will be weakened.
This is because not only the particles are destroyed during drying and the particle size distribution becomes broader, but also the production of non-spherical particles increases. When the dispersed particle size of the colloidal liquid used in the present invention is 120 Å or less, solid spheres as described below can be obtained. According to the present invention, the raw colloidal liquid has a temperature of 10°C.
It is sprayed into a dry atmosphere in the range of ~100°C and 3-13% humidity. Humidity here refers to the percentage of water vapor and volume that occupies a dry atmosphere. As the spraying means, a spray nozzle commonly used in spray drying methods can be used, but it is preferable to use a commonly used two-fluid nozzle. It is appropriate that the volume ratio of the amount of air to be ejected to the amount of raw material colloid (hereinafter referred to as gas-liquid ratio) is 10,000 to 500:1. In the case of the present invention, the atmosphere in which the raw material colloid droplets are dried, in other words, the drying space, has a temperature of 10°C to
Must be maintained at 100°C and humidity between 3 and 13%. If the drying atmosphere temperature exceeds the above range, even if the humidity is relatively high, such as 13%, the drying rate of the droplets will be too fast and the shape of the dried particles will not be spherical. Furthermore, if the drying temperature is below the above range, the droplets dry slowly and cannot be dried in a practical scale drying space. Regarding the humidity of the drying atmosphere, since the drying temperature employed in the present invention is relatively low, it is necessary to maintain the humidity between 3 and 13%. By the way, if a colloidal liquid sprayed with a two-fluid nozzle is dried in an atmosphere under the conditions described above, the rate at which the colloidal dispersion medium evaporates from the surface of the droplet and the colloidal dispersion medium inside the droplet on the surface will increase. Since the rate of diffusion is appropriately balanced, the droplets are dried while maintaining the shape as sprayed. Since the droplets are finely divided by the two-fluid nozzle, according to the present invention, the average particle size is 1 to 1.
It is possible to produce particles that are in the range of 20μ, have a sharp particle size distribution, and have a sphericity of 0.850 to 1.00. Here, sphericity refers to particles obtained by spray drying that are dispersed so that they do not overlap each other, and then an electron micrograph is taken with a scanning electron microscope (SEM) magnified 2000 times. The image is analyzed with an analyzer to measure the area and circumference of the projected surface of each particle, and the equivalent diameter is calculated from the area assuming that it is a perfect circle, and the equivalent diameter is calculated from the circumference assuming that it is a perfect circle. The equivalent diameter was defined as Hd, and the ratio of the two was defined as sphericity. Sphericity = HD (equivalent diameter from area) / Hd (equivalent diameter from circumference) According to the present invention, 90% of particles have a sphericity in the range of 0.850 to 1.00 as defined above. Such a powder can be obtained with a yield higher than that and is referred to as a truly spherical powder in the present invention. As a matter of course, if the particles are stuck together or if the particles have depressions, the sphericity is outside the above range even if the particles are recognized to be perfectly spherical as a whole. As mentioned above, in the method of the present invention, the average particle diameter of the dispersed colloid particles is 120 mm as the raw colloid liquid.
By using a colloidal liquid having a density of Å or less, solid spheres with a large bulk density can be manufactured. If the average particle size of the colloid particles is within the range of 120 Å or less, and a colloid liquid with a relatively large average particle size and a colloid liquid with a relatively small average particle size are mixed and used, the bulk density of the solid sphere can be further increased. Here, a solid sphere has a pore volume of 0.15 ml/g or less and a bulk density of 0.8 g/g.
Refers to true spherical particles larger than ml. To be sure, the bulk density of the solid sphere obtained by the present invention is approximately equal to the bulk density calculated from the porosity (0.36) when true spheres are packed closest. [Example] Example 1 Silica concentration 30 prepared from sodium silicate solution and sulfuric acid
%, a silica colloidal liquid with an average particle size of 70 Å was supplied to one side of a commercially available two-fluid nozzle at a flow rate of 5 kg/hr,
On the other hand, gas pressure was supplied at a flow rate of 2 Kg/hr, and the colloidal liquid was sprayed into the drying space through which the drying air flow was flowing. Table 1 shows the temperature and humidity of the drying space where the colloidal liquid is sprayed and the properties of the obtained dry particles.
【表】
実施例 ２
水ガラスを水で希釈した後、イオン交換樹脂で
処理して珪酸液を得、この珪酸液を加熱する方法
により、シリカ濃度のコロイド粒子の平均粒径
（一次粒子）が異なる幾つかのシリカコロイド液
を調製した。
それぞれのシリカコロイド液と加圧気体を、実
施例１と同じ二流体ノズルに同じ条件で供給して
噴霧乾燥した。乾燥空間を流れる乾燥気流の温度
及び湿度と、噴霧したコロイド液の性状を表−
2Aに、また乾燥粒子の性状を表−2Bに示す。[Table] Example 2 After diluting water glass with water, it is treated with an ion exchange resin to obtain a silicic acid solution, and by heating this silicic acid solution, the average particle size (primary particles) of colloidal particles with a silica concentration is Several different silica colloid solutions were prepared. Each silica colloid liquid and pressurized gas were supplied to the same two-fluid nozzle as in Example 1 under the same conditions and spray-dried. Table shows the temperature and humidity of the drying air flowing through the drying space and the properties of the sprayed colloid liquid.
Table 2A shows the properties of the dried particles, and Table 2B shows the properties of the dried particles.
【表】
表−2A及び2Bから明らかな通り、本発明の方
法によれば、分散粒子の平均粒径が2500Å以下で
あるコロイド液を噴霧することにより、平均粒径
１〜20μの真球状シリカ粒子を得ることができ、
分散粒子の平均粒径が120Å以下のコロイド液を
噴霧すれば、シリカの中実球を得ることができ
る。第１図に実験No.２−９で得たシリカ粉末の電
子顕微鏡写真を示す。
実施例 ３
エチルシリケート試薬にエチルアルコールとア
ンモニア水を加えて加水分解し、分散粒子の平均
粒径が70Åであり、分散媒がエチルアルコールで
あるシリカコロイド液を得た。このコロイド液を
乾燥気流温度40℃、湿度9.8％の乾燥雰囲気に実
施例１と同様な方法で噴霧し、平均粒径8.3μ、粒
度分布0.5〜17μ、細孔容積0.07ml／ｇ、嵩密度
1.02ｇ／mlの真球状シリカ粉末（中実球）を得
た。
実施例 ４
分散粒子の平均粒径が120Åであるシリカコロ
イド液をシリカ分として200ｇ、分散粒子の平均
粒径が20Åであるシリカコロイド液をシリカ分と
して100ｇそれぞれ採取し、これらの混合液を乾
燥気流温度60℃、湿度9.8％の乾燥雰囲気に実施
例１と同様な方法で噴霧して、平均粒径10μ、粒
度分布0.5〜20μ、細孔容積0.11ml／ｇ、嵩密度
1.01ｇ／mlの真球状シリカ粉末（中実球）を得
た。
実施例 ５
2.5％に希釈した塩化アルミニウムに、３％に
希釈した苛性ソーダ水溶液を添加し、PH7.5に中
和して得た沈殿を洗浄脱塩する。この沈殿に硝酸
を加えて解膠し、分散粒子の平均粒径が154Åで
あるアルミナコロイド液を調製した。このコロイ
ド液を乾燥気流温度60℃、湿度9.8％の乾燥雰囲
気に実施例１と同様な方法で噴霧して、平均粒径
10μ、粒度分布１〜18μの真球状アルミナ粉末を
得た。
実施例 ６
３％に希釈したメタチタン酸にアンモニア水を
加えてPH８に調整し、得られた沈殿を洗浄脱塩す
る。この沈殿に第４級アミンを添加してから、95
℃で１時間加温して分散粒子の平均粒径が480Å
である酸化チタンコロイド液を得た。このコロイ
ド液を乾燥気流温度60℃、湿度9.8％の乾燥雰囲
気に実施例１の同様な方法で噴霧して、平均粒径
12μ、粒度分布１〜20μの真球状酸化チタン粉末
を得た。
実施例 ７
塩化第二鉄を加水分解して得られた酸化鉄コロ
イド液（分散粒子の平均粒径480Å）を、乾燥気
流温度60℃、湿度9.8％の乾燥雰囲気に実施例１
と同様な方法で噴霧して、平均粒径8μ、粒度分
布１〜18μの真球状粉末を得た。
実施例 ８
硫酸ジルコニルにアンモニア水を加えて加水分
解し、分散粒子の平均粒径が230Åである酸化ジ
ルコニウムコロイド液を得た。このコロイド液を
乾燥気流温度60℃、湿度9.8％の乾燥雰囲気に実
施例１と同様な方法で噴霧し、平均粒径9μ、粒
度分布0.5〜20μの真球状粉末を得た。
実施例 ９
98％三酸化アンチモン試薬を水に分散させ、こ
れに過酸化水素を加えて120℃で10分間加熱後、
濃度10％に濃縮して分散粒子の平均粒径が245Å
の酸化アンチモンコロイド液を得た。このコロイ
ド液を乾燥気流温度60℃、湿度9.8％の乾燥雰囲
気に実施例１と同様な方法で噴霧し、平均粒径
8μ、粒度分布0.5〜16μの真球状粉末を得た。
実施例 10
塩化第二錫にアンモニア水を加えて加水分解
し、分散粒子の平均粒径が203Åである酸化スズ
コロイド液を得た。このコロイド液を乾燥気流温
度60℃、湿度9.8％の乾燥雰囲気に実施例１と同
様な方法で噴霧し、平均粒径7μ、粒度分布0.5〜
15μの真球状粉末を得た。
尚、上記の各実施例に於いて、コロイド液に分
散する粒子の平均粒径は、一次粒子の平均粒径で
あり、噴霧乾燥して得られた粉末の粒径及び粒度
分布は、電子顕微鏡による画像解析法にて測定し
た。また、粉末の細孔容積は、電気炉にて粉末を
400℃で２時間前処理し、窒素吸着法で測定した。
嵩密度は200c.c.のメスシリンダーに粉末を約100c.c.
収めて振動させ、粉末が占める容積が最小になつ
た際の容積と、その重量から算出した。
［発明の効果］
本発明の方法は無機酸化物及び／又は含水酸化
物が平均粒径2500Å以下で分散するコロイド液
を、極めて温和な条件下で噴霧乾燥するものであ
るので、無機酸化物及び／又は含水酸化物からな
る微細で、しかも真球状の粉末を、シヤープな粒
度分布で製造することができる。そして、分散粒
子の平均粒径が120Å以下であるコロイド液を使
用すれば、細孔容積が小さく、嵩密度が大きい粉
末を得ることができる。
本発明の方法で得られる粉末は、細かいうえに
真球状であるため、化粧品材料として、あるいは
また合成樹脂充填剤として使用することができ
る。[Table] As is clear from Tables 2A and 2B, according to the method of the present invention, true spherical silica with an average particle size of 1 to 20 μm can be obtained by spraying a colloidal liquid in which the average particle size of dispersed particles is 2500 Å or less. particles can be obtained,
By spraying a colloidal liquid whose dispersed particles have an average particle size of 120 Å or less, solid silica spheres can be obtained. FIG. 1 shows an electron micrograph of the silica powder obtained in Experiment No. 2-9. Example 3 Ethyl alcohol and aqueous ammonia were added to an ethyl silicate reagent and hydrolyzed to obtain a silica colloid liquid in which the average particle size of dispersed particles was 70 Å and the dispersion medium was ethyl alcohol. This colloidal liquid was sprayed in a dry atmosphere with a dry air flow temperature of 40°C and a humidity of 9.8% in the same manner as in Example 1, with an average particle size of 8.3μ, a particle size distribution of 0.5 to 17μ, a pore volume of 0.07ml/g, and a bulk density.
A true spherical silica powder (solid sphere) of 1.02 g/ml was obtained. Example 4 200 g of a silica colloidal liquid with an average particle size of dispersed particles of 120 Å was collected as a silica content, and 100 g of a silica colloidal liquid with an average particle size of dispersed particles of 20 Å were collected as a silica content, and these mixed liquids were dried. It was sprayed in a dry atmosphere with an air flow temperature of 60°C and a humidity of 9.8% in the same manner as in Example 1 to obtain an average particle size of 10μ, a particle size distribution of 0.5 to 20μ, a pore volume of 0.11ml/g, and a bulk density.
A true spherical silica powder (solid sphere) of 1.01 g/ml was obtained. Example 5 A caustic soda aqueous solution diluted to 3% is added to aluminum chloride diluted to 2.5%, and the precipitate obtained by neutralizing to pH 7.5 is washed and desalted. This precipitate was peptized by adding nitric acid to prepare an alumina colloid solution in which the average particle size of dispersed particles was 154 Å. This colloidal liquid was sprayed in a dry atmosphere with a dry air flow temperature of 60°C and a humidity of 9.8% in the same manner as in Example 1, and the average particle size was
A truly spherical alumina powder with a diameter of 10μ and a particle size distribution of 1 to 18μ was obtained. Example 6 Aqueous ammonia is added to metatitanic acid diluted to 3% to adjust the pH to 8, and the resulting precipitate is washed and desalted. After adding quaternary amine to this precipitate, 95
After heating at ℃ for 1 hour, the average particle size of the dispersed particles was 480 Å.
A titanium oxide colloid liquid having the following properties was obtained. This colloidal liquid was sprayed in a dry atmosphere with a dry air flow temperature of 60°C and a humidity of 9.8% in the same manner as in Example 1, and the average particle size was
A truly spherical titanium oxide powder with a diameter of 12μ and a particle size distribution of 1 to 20μ was obtained. Example 7 Iron oxide colloidal liquid (average particle size of dispersed particles 480 Å) obtained by hydrolyzing ferric chloride was placed in a dry atmosphere with a dry air flow temperature of 60°C and humidity of 9.8% Example 1
A perfectly spherical powder with an average particle diameter of 8 microns and a particle size distribution of 1 to 18 microns was obtained by spraying in the same manner as above. Example 8 Zirconyl sulfate was hydrolyzed by adding aqueous ammonia to obtain a colloidal zirconium oxide solution in which the average particle size of dispersed particles was 230 Å. This colloidal liquid was sprayed into a dry atmosphere with a dry air flow temperature of 60° C. and a humidity of 9.8% in the same manner as in Example 1 to obtain a truly spherical powder with an average particle size of 9 μm and a particle size distribution of 0.5 to 20 μm. Example 9 98% antimony trioxide reagent was dispersed in water, hydrogen peroxide was added thereto, and after heating at 120°C for 10 minutes,
When concentrated to a concentration of 10%, the average particle size of the dispersed particles is 245 Å.
An antimony oxide colloid solution was obtained. This colloidal liquid was sprayed in a dry atmosphere with a dry air flow temperature of 60°C and a humidity of 9.8% in the same manner as in Example 1, and the average particle size was
A perfectly spherical powder with a diameter of 8μ and a particle size distribution of 0.5 to 16μ was obtained. Example 10 Aqueous ammonia was added to tin chloride and hydrolyzed to obtain a tin oxide colloidal solution in which the average particle size of dispersed particles was 203 Å. This colloidal liquid was sprayed in a dry atmosphere with a dry air flow temperature of 60°C and a humidity of 9.8% in the same manner as in Example 1, and the average particle size was 7μ and the particle size distribution was 0.5~
A perfectly spherical powder of 15μ was obtained. In each of the above examples, the average particle size of the particles dispersed in the colloidal liquid is the average particle size of the primary particles, and the particle size and particle size distribution of the powder obtained by spray drying are determined by electron microscopy. Measured using image analysis method. In addition, the pore volume of the powder can be determined by
It was pretreated at 400°C for 2 hours and measured by nitrogen adsorption method.
The bulk density is approximately 100 c.c. of powder in a graduated cylinder of 200 c.c.
The powder was stored and vibrated, and the volume was calculated from the minimum volume occupied by the powder and its weight. [Effects of the Invention] The method of the present invention spray-dries a colloidal liquid in which inorganic oxides and/or hydrous oxides are dispersed with an average particle size of 2500 Å or less under extremely mild conditions. A fine and truly spherical powder made of a hydrous oxide and/or a hydrated oxide can be produced with a sharp particle size distribution. If a colloidal liquid in which the average particle diameter of dispersed particles is 120 Å or less is used, a powder with a small pore volume and a large bulk density can be obtained. Since the powder obtained by the method of the invention is fine and spherical, it can be used as a cosmetic material or as a filler for synthetic resins.
第１図は実施例２の実験２−９で得られたシリ
カ粉末粒子構造の電子顕微鏡写真である。
FIG. 1 is an electron micrograph of the silica powder particle structure obtained in Experiment 2-9 of Example 2.
Claims (1)
分散質とし、その分散質の平均粒径（一次粒子）
が2500Å以下であるコロイド液を、温度10〜100
℃、湿度３〜13％の乾燥雰囲気内に噴霧して乾燥
することを特徴とする平均粒径が１〜20μの範囲
にある真球状の無機酸化物粉末及び／又は含水酸
化物粉末を製造する方法。 ２ 分散質の平均粒径（一次粒子）が120Å以下
であるコロイド液を使用して、平均粒径１〜
20μ、細孔容積0.15ml／ｇ以下、嵩密度0.8ｇ／ml
以上の粉末を製造する特許請求の範囲第１項記載
の方法。 ３ コロイド液と分散質が珪素、アルミニウム、
チタニウム、ジルコニウム、アンチモン、スズ、
鉄、亜鉛及びマグネシウムから選ばれる単一元素
の酸化物及び／又は含水酸化物である特許請求の
範囲第１項又は第２項記載の方法。[Scope of Claims] 1 A single type of inorganic oxide and/or hydrous oxide is used as a dispersoid, and the average particle size of the dispersoid (primary particles)
A colloidal liquid with a diameter of 2500 Å or less is heated at a temperature of 10 to 100 Å.
To produce a truly spherical inorganic oxide powder and/or hydrous oxide powder with an average particle size in the range of 1 to 20μ, characterized by spraying and drying in a dry atmosphere at a temperature of 3 to 13% humidity. Method. 2 Using a colloidal liquid in which the average particle size (primary particles) of the dispersoid is 120 Å or less,
20μ, pore volume 0.15ml/g or less, bulk density 0.8g/ml
A method according to claim 1 for producing the above powder. 3 Colloid liquid and dispersoid are silicon, aluminum,
titanium, zirconium, antimony, tin,
3. The method according to claim 1 or 2, wherein the oxide is an oxide and/or a hydrous oxide of a single element selected from iron, zinc and magnesium.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1171685 | 1985-01-23 | ||
| JP60-11716 | 1985-01-23 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61270201A JPS61270201A (en) | 1986-11-29 |
| JPH0343202B2 true JPH0343202B2 (en) | 1991-07-01 |
Family
ID=11785763
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61012658A Granted JPS61270201A (en) | 1985-01-23 | 1986-01-23 | Production of spherical inorganic oxide powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61270201A (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0811681B2 (en) * | 1986-01-21 | 1996-02-07 | 三菱化学株式会社 | Method for producing spherical metal oxide particles |
| JPS63103812A (en) * | 1986-10-20 | 1988-05-09 | Toshiba Silicone Co Ltd | Truly spherical silica powder and production thereof |
| JP3791936B2 (en) * | 1994-08-26 | 2006-06-28 | 触媒化成工業株式会社 | Inorganic oxide particles |
| KR100490234B1 (en) * | 2001-03-28 | 2005-05-17 | 가부시키 가이샤 닛코 마테리알즈 | Manufacturing method of ito powder with tin dissolved in indium oxide, and manufacturing method of ito target |
| JP4729914B2 (en) * | 2004-12-09 | 2011-07-20 | 株式会社豊田中央研究所 | Fine iron oxide powder and method for producing the same |
| EP2025720B1 (en) * | 2007-08-13 | 2010-12-08 | Procter & Gamble International Operations SA | Spray-drying process for the manufacture of dye-loaded particles |
| JP5631530B2 (en) | 2007-12-07 | 2014-11-26 | 日揮触媒化成株式会社 | Porous silica-based particles having surface smoothness, a method for producing the same, and a cosmetic comprising the porous silica-based particles |
| JP5199023B2 (en) * | 2008-10-24 | 2013-05-15 | 三井金属鉱業株式会社 | Tin oxide powder |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4983959A (en) * | 1972-11-29 | 1974-08-13 | ||
| JPS59169927A (en) * | 1983-02-25 | 1984-09-26 | モンテディソン・エッセ・ピ・ア | Method and apparatus for manufacturing single dispersive andnon-aggregative spherical metal oxide smaller than one micron in diameter |
-
1986
- 1986-01-23 JP JP61012658A patent/JPS61270201A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4983959A (en) * | 1972-11-29 | 1974-08-13 | ||
| JPS59169927A (en) * | 1983-02-25 | 1984-09-26 | モンテディソン・エッセ・ピ・ア | Method and apparatus for manufacturing single dispersive andnon-aggregative spherical metal oxide smaller than one micron in diameter |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61270201A (en) | 1986-11-29 |
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