JPH0725614A - Ultrafine zinc oxide particle and production thereof - Google Patents
Ultrafine zinc oxide particle and production thereofInfo
- Publication number
- JPH0725614A JPH0725614A JP19312893A JP19312893A JPH0725614A JP H0725614 A JPH0725614 A JP H0725614A JP 19312893 A JP19312893 A JP 19312893A JP 19312893 A JP19312893 A JP 19312893A JP H0725614 A JPH0725614 A JP H0725614A
- Authority
- JP
- Japan
- Prior art keywords
- zinc oxide
- ultrafine particles
- oxide ultrafine
- raw material
- light transmittance
- 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.)
- Pending
Links
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、酸化亜鉛超微粒子及び
その製造方法に関する。更に詳しくは、亜鉛を含む金属
化合物を気化させ原料ガスとし、該原料ガスの熱分解反
応及び酸化反応により得られる酸化亜鉛超微粒子及びそ
の製造方法に関する。TECHNICAL FIELD The present invention relates to zinc oxide ultrafine particles and a method for producing the same. More specifically, the present invention relates to zinc oxide ultrafine particles obtained by vaporizing a metal compound containing zinc as a raw material gas and performing a thermal decomposition reaction and an oxidation reaction of the raw material gas, and a method for producing the same.
【０００２】[0002]
【従来の技術および発明が解決しようとする課題】一般
に、酸化亜鉛（ＺｎＯ）微粒子は、種々の工業製品、医
薬品、ゴムの加硫促進剤、触媒、バリスター（可変抵抗
器）、塗料等に用いられ、最近では紫外線遮蔽材として
ＵＶ化粧品にも用いられ、これらの他にも様々の工業分
野に応用されている。従って、酸化亜鉛微粒子は非常に
有用な工業的価値を有するが、酸化亜鉛微粒子の有する
機能を大きく、飛躍的に発現させる為には超微粒子化が
重要である。すなわち、超微粒子化することにより、比
表面積が極めて大きく増加し、微粒子を構成する全分子
数中に占める微粒子表面に位置する分子の数の割合が大
きくなって微粒子の表面エネルギーが増大するため、そ
の機能が極めて大きく発現される。2. Description of the Related Art In general, zinc oxide (ZnO) fine particles are used in various industrial products, pharmaceuticals, rubber vulcanization accelerators, catalysts, varistors (variable resistors), paints and the like. It has been used for UV cosmetics as an ultraviolet shielding material recently, and has been applied to various industrial fields besides these. Therefore, although zinc oxide fine particles have a very useful industrial value, it is important to make them ultrafine particles in order to bring out the function of the zinc oxide fine particles to a great extent and to be dramatically exhibited. That is, by forming ultrafine particles, the specific surface area is extremely increased, the ratio of the number of molecules located on the surface of the fine particles in the total number of molecules forming the fine particles is increased, and the surface energy of the fine particles is increased. The function is extremely greatly expressed.
【０００３】このように極めて重要な工業的価値を有す
ると考えられる酸化亜鉛超微粒子の製造は、液相法と気
相法に大別できる。液相法では、例えば、塩酸亜鉛、硝
酸亜鉛、または硫酸亜鉛を含有する水溶液を蓚酸、蓚酸
アルカリまたは蓚酸アンモニウムの水溶液中に滴下し、
生ずる沈澱を濾別捕集し、３５０〜５５０℃の温度範囲
の酸素２０％以上を含有する酸化性ガス雰囲気中で０．
５〜３時間置き、平均粒径２０〜５０ｎｍの超微粒子状
酸化亜鉛粉末を得る方法（特開昭５７−２０５３１９号
公報）がある。しかし、このような液相法による製造プ
ロセスについては、バッチ式が基本となる為に自動化が
困難であり、しかも生成微粒子は固液混相の状態で得ら
れる為、製品として得るには、濾過、乾燥の工程が必要
となる。従って、製造プロセス全体が複雑となりプロセ
ス全体のメンテナンスが難しく、その為に製品の低コス
ト化が困難となる。また、濾過、乾燥工程を経ても、超
微粒子の表面には溶媒分子が不純物として残存しやす
く、超微粒子の純度及び分散性の点で良くない。As described above, the production of zinc oxide ultrafine particles, which are considered to have extremely important industrial value, can be roughly classified into a liquid phase method and a gas phase method. In the liquid phase method, for example, an aqueous solution containing zinc chloride, zinc nitrate, or zinc sulfate is added dropwise to an aqueous solution of oxalic acid, alkali oxalate or ammonium oxalate,
The resulting precipitate was collected by filtration, and the precipitate was collected in a temperature range of 350 to 550 ° C. in an oxidizing gas atmosphere containing 20% or more of oxygen.
There is a method (Japanese Patent Application Laid-Open No. 57-205319) for obtaining ultrafine zinc oxide powder having an average particle size of 20 to 50 nm after standing for 5 to 3 hours. However, with regard to the manufacturing process by such a liquid phase method, it is difficult to automate because the batch system is basically used, and moreover, the generated fine particles can be obtained in a solid-liquid mixed phase state, so to obtain a product, filtration, A drying process is required. Therefore, the entire manufacturing process becomes complicated, and maintenance of the entire process is difficult, which makes it difficult to reduce the cost of the product. Further, solvent molecules are likely to remain as impurities on the surface of the ultrafine particles even after the filtration and drying steps, which is not good in terms of purity and dispersibility of the ultrafine particles.
【０００４】気相法では、一般に金属を蒸気化し、その
蒸気と酸素を有するガスとを混合して接触酸化反応させ
ることにより、セラミックス微粒子を得る方法（例え
ば、酸化亜鉛微粒子の製造では、特開平１−２８６９１
９号公報）がある。また、気相法の一手法として、ＣＶ
Ｄ法（気相化学成長法）と呼ばれる微粒子製造方法があ
るが、これは原料ガスをキャリアーガスと共に、反応管
へ導入して、内部で原料ガスの化学反応により微粒子を
生成させる方法であり、製品純度が高く、また比較的粒
子径がそろっていること等が挙げられる。例えば、揮発
性金属化合物を気化または霧化せしめた後、加熱下に分
解して金属酸化物超微粒子とし、分解後直ちに前記金属
酸化物超微粒子が再び合体しない温度まで冷却すること
を特徴とする球状金属酸化物超微粒子の製造方法（特開
昭６１−２０１６０４号公報）がある。In the gas phase method, a metal is generally vaporized, and the vapor and a gas containing oxygen are mixed to carry out a catalytic oxidation reaction to obtain ceramic fine particles (for example, in the production of zinc oxide fine particles, a method described in Japanese Patent Laid-Open Publication No. H11-242242) is used. 1-28691
No. 9). In addition, as one method of the vapor phase method, CV
There is a method for producing fine particles called the D method (vapor phase chemical growth method), which is a method in which a raw material gas is introduced into a reaction tube together with a carrier gas and fine particles are generated by a chemical reaction of the raw material gas inside, It can be mentioned that the product has high purity and that the particle sizes are relatively uniform. For example, the volatile metal compound is vaporized or atomized, and then decomposed under heating into metal oxide ultrafine particles, and immediately after the decomposition, the metal oxide ultrafine particles are cooled to a temperature at which they do not coalesce again. There is a method for producing spherical metal oxide ultrafine particles (Japanese Patent Laid-Open No. 61-201604).
【０００５】前述の気相法による製造プロセスについて
は、プロセスの操作条件の自由度が低いという問題があ
る。すなわち亜鉛蒸気と空気との接触酸化反応における
反応速度や反応率、生成粒子の大きさ及び結晶性等を制
御するのが難しく、特に超微粒子化するには亜鉛蒸気濃
度を極度に低く設定する必要があるが、この場合では超
微粒子の生産性が悪くなる。また、一般に亜鉛蒸気は毒
性が極めて強く、製造プロセスの安全性の面からも好ま
しくない。The above-mentioned manufacturing process by the vapor phase method has a problem in that the degree of freedom in operating conditions of the process is low. That is, it is difficult to control the reaction rate and reaction rate in the catalytic oxidation reaction between zinc vapor and air, the size and crystallinity of the produced particles, and it is necessary to set the zinc vapor concentration to an extremely low level especially for ultrafine particles. However, in this case, the productivity of ultrafine particles is deteriorated. Further, zinc vapor is generally extremely toxic, which is not preferable from the viewpoint of safety of the manufacturing process.
【０００６】前述のＣＶＤ法による製造プロセスについ
ては、揮発性金属化合物の熱分解反応を利用して球状の
金属酸化物超微粒子を製造するが、熱分解反応だけでは
生成する超微粒子の分子内に酸素格子欠陥が生じやす
く、結晶性も良くない。従って、熱分解反応と並行して
金属の酸化反応も進行させることが必要であり、その為
には揮発性金属化合物の分子内の酸素源だけでなく、キ
ャリアーガス中に酸素を含有させることにより、揮発性
金属化合物の熱分解反応及び酸化反応を促進させなけれ
ばならない。また、前述の特開昭６１−２０１６０４号
公報においては、生成する金属酸化物超微粒子の種類に
おいて酸化亜鉛超微粒子についての記載は全くなく、ま
た酸化亜鉛超微粒子の光学的機能、特に可視光透過機能
及び紫外線遮蔽機能における特性についても記載は全く
ない。In the above-mentioned CVD process, spherical metal oxide ultrafine particles are produced by utilizing the thermal decomposition reaction of a volatile metal compound. Oxygen lattice defects easily occur and the crystallinity is not good. Therefore, it is necessary to proceed with the metal oxidation reaction in parallel with the thermal decomposition reaction. For that purpose, not only the oxygen source in the molecule of the volatile metal compound but also oxygen is contained in the carrier gas. , It is necessary to promote the thermal decomposition reaction and oxidation reaction of volatile metal compounds. Further, in the above-mentioned Japanese Patent Laid-Open No. 61-201604, there is no mention of zinc oxide ultrafine particles in the type of metal oxide ultrafine particles produced, and the optical function of the zinc oxide ultrafine particles, particularly visible light transmission. There is no description about the characteristics of the function and the ultraviolet shielding function.
【０００７】上記以外にも、気相法と液相法の両者の特
徴を有する噴霧熱分解法と呼ばれる方法がある。例え
ば、金属塩を含む溶液を液滴径が０．１μｍから１００
μｍの微小な液滴とし、その液滴をキャリアーガスを用
いて気液混相の状態で高温反応炉内へ送り、該反応炉内
部で液滴に含まれる金属塩を熱分解して金属酸化物微粒
子を生成し、得られた金属酸化物微粒子を静電捕集器を
用いて回収することを特徴とする金属酸化物微粒子の製
造方法（特願平２−４０９２２９号）がある。In addition to the above, there is a method called a spray pyrolysis method which has the characteristics of both the vapor phase method and the liquid phase method. For example, a solution containing a metal salt may have a droplet diameter of 0.1 μm to 100 μm.
A fine droplet of μm, which is sent into a high-temperature reaction furnace in a gas-liquid mixed phase state using a carrier gas, and the metal salt contained in the droplet is thermally decomposed inside the reaction furnace to form a metal oxide. There is a method for producing metal oxide fine particles (Japanese Patent Application No. 2-409229), which comprises producing fine particles and collecting the obtained metal oxide fine particles using an electrostatic collector.
【０００８】前述の噴霧熱分解法による製造では、０．
２μｍ以下の超微粒子を製造する際、金属塩を含む噴霧
溶液において金属塩濃度を極度に低くする必要があり、
これでは生成する金属酸化物超微粒子の生成量も極めて
少なく、またエネルギー効率の点からも良くないと言え
る。従って、上記の従来技術を考えた場合、平均粒子径
が０．００５〜０．２μｍであって実質的に球状である
酸化亜鉛超微粒子を、簡便な方法により連続して安価に
製造する方法の開発が課題となっていた。また、酸化亜
鉛超微粒子の光学的機能として、可視光域（光波長４０
０〜８００ｎｍ）における高い透明性、及び紫外線Ｂ，
Ａ領域（光波長２９０〜４００ｎｍ）における高い遮蔽
性を有するものの開発が課題となっていた。In the production by the above-mentioned spray pyrolysis method,
When producing ultrafine particles of 2 μm or less, it is necessary to extremely reduce the metal salt concentration in the spray solution containing the metal salt,
In this case, the amount of ultrafine metal oxide particles produced is extremely small, and it can be said that it is not good in terms of energy efficiency. Therefore, considering the above-mentioned conventional technique, a method for continuously and inexpensively producing zinc oxide ultrafine particles having an average particle size of 0.005 to 0.2 μm and being substantially spherical by a simple method. Development was a challenge. Further, as an optical function of the zinc oxide ultrafine particles, a visible light region (light wavelength 40
High transparency in 0-800 nm), and ultraviolet B,
The development of a material having a high shielding property in the A region (light wavelength 290 to 400 nm) has been a problem.
【０００９】[0009]
【課題を解決するための手段】本発明は、亜鉛を含む金
属化合物を気化させ原料ガスとし、該原料ガスを酸素を
含むキャリアーガスを用いて高温の反応管へ導入し、該
反応管内部で熱分解反応及び酸化反応させることにより
酸化亜鉛超微粒子を製造するという簡便な方法により、
酸化亜鉛超微粒子を連続して安価に製造できることを見
い出し、また、その方法による酸化亜鉛超微粒子が可視
光域における高透明性、及び紫外線Ｂ，Ａ領域における
高遮蔽性を有していることを見い出し、さらに鋭意研究
を進めて本発明を完成した。According to the present invention, a metal compound containing zinc is vaporized into a raw material gas, and the raw material gas is introduced into a high-temperature reaction tube by using a carrier gas containing oxygen. By a simple method of producing zinc oxide ultrafine particles by a thermal decomposition reaction and an oxidation reaction,
It was found that zinc oxide ultrafine particles can be continuously produced at low cost, and that the zinc oxide ultrafine particles produced by the method have high transparency in the visible light region and high shielding properties in the ultraviolet B and A regions. The present invention was completed by discovering it and further conducting intensive research.
【００１０】すなわち、本発明の要旨は、（１）亜鉛を
含む金属化合物を気化させ原料ガスとし、該原料ガスを
酸素を含むキャリアーガスを用いて高温の反応管へ導入
し、該反応管内部で該原料ガスを熱分解反応及び酸化反
応させることにより得られる、平均粒子径が０．００５
〜０．２μｍであって実質的に球状である酸化亜鉛超微
粒子、および（２）亜鉛を含む金属化合物を気化させ原
料ガスとし、該原料ガスを酸素を含むキャリアーガスを
用いて高温の反応管へ導入し、該反応管内部で該原料ガ
スを熱分解反応及び酸化反応させることにより、平均粒
子径が０．００５〜０．２μｍであって実質的に球状で
ある酸化亜鉛超微粒子を連続的に製造することを特徴と
する酸化亜鉛超微粒子の製造方法、に関する。That is, the gist of the present invention is as follows: (1) A metal compound containing zinc is vaporized into a raw material gas, and the raw material gas is introduced into a high-temperature reaction tube by using a carrier gas containing oxygen. And an average particle size of 0.005 obtained by subjecting the raw material gas to a thermal decomposition reaction and an oxidation reaction.
-0.2 μm and substantially spherical zinc oxide ultrafine particles, and (2) a metal compound containing zinc is vaporized as a raw material gas, and the raw material gas is a high temperature reaction tube using a carrier gas containing oxygen. And the raw material gas is subjected to a thermal decomposition reaction and an oxidation reaction inside the reaction tube to continuously produce zinc oxide ultrafine particles having an average particle diameter of 0.005 to 0.2 μm and being substantially spherical. And a method for producing ultrafine zinc oxide particles.
【００１１】以下、図面に基づき、本発明について詳細
に説明する。図１は、本発明の製造方法に好適に用いら
れる装置の一例の概略図を示すものである。原料気化装
置１において気化された亜鉛を含む金属化合物からなる
原料ガスを酸素を含むキャリアーガス供給装置２より供
給されるキャリアーガスにより、加熱体３を有する高温
の反応管４に導入する。反応管４の内部では、該原料ガ
スの熱分解反応及び酸化反応により、酸化亜鉛超微粒子
が生成する。反応管４より出た気固混相状態の酸化亜鉛
超微粒子は捕集装置５で回収される。The present invention will be described in detail below with reference to the drawings. FIG. 1 is a schematic view showing an example of an apparatus preferably used in the manufacturing method of the present invention. A raw material gas consisting of a metal compound containing zinc vaporized in the raw material vaporizer 1 is introduced into a high temperature reaction tube 4 having a heating body 3 by a carrier gas supplied from a carrier gas supply device 2 containing oxygen. Inside the reaction tube 4, zinc oxide ultrafine particles are generated by a thermal decomposition reaction and an oxidation reaction of the raw material gas. The zinc oxide ultrafine particles in the gas-solid mixed phase, which have flowed out from the reaction tube 4, are collected by the collector 5.
【００１２】原料気化装置１は、温度制御可能な発熱体
を有する蒸発器型等が好ましく、特に原料の蒸発量を一
定にできるものが良い。キャリアーガス供給装置２は、
長時間にわたり一定流量のキャリアーガスを供給できる
ようなものであればよく、その流量制御装置としては、
例えば質量式流量計が使用できる。加熱体３の形状及び
種類は、特に限定されないが、一定温度を長時間にわた
り保持できるようなものが好ましい。加熱体の材質に
は、例えば、カンタル線等が使用できる。反応管４の形
状は、特に限定されないが、反応管内での温度分布が均
一になれば良く、その観点から円筒型等が好ましい。反
応管の材質には、例えばステンレス、セラミックス、石
英ガラス等が使用できる。生成超微粒子の捕集装置５に
は、フィルター式、静電捕集式等が有効であるが、長期
運転用には、電気集塵器または拡散荷電型等の静電捕集
式が好ましい。The raw material vaporizer 1 is preferably an evaporator type having a heating element whose temperature is controllable, and in particular, one which can keep the amount of raw material evaporated is good. The carrier gas supply device 2 is
As long as it can supply a carrier gas at a constant flow rate for a long time, the flow rate control device is
For example, a mass flow meter can be used. The shape and type of the heating element 3 are not particularly limited, but those capable of maintaining a constant temperature for a long time are preferable. For the material of the heating body, for example, Kanthal wire or the like can be used. The shape of the reaction tube 4 is not particularly limited, but it is sufficient if the temperature distribution in the reaction tube is uniform, and from this viewpoint, a cylindrical shape or the like is preferable. As the material of the reaction tube, for example, stainless steel, ceramics, quartz glass or the like can be used. The collection device 5 for the generated ultrafine particles is effectively a filter type or an electrostatic collection type, but for long-term operation, an electrostatic collection type such as an electrostatic precipitator or a diffusion charging type is preferable.
【００１３】次に、このような装置を用いた本発明の酸
化亜鉛超微粒子の製造方法について説明する。原料であ
る亜鉛を含む金属化合物としては、塩化物、水素化物
や、アルコキシド、アルキル化物、β−ジケトン化物等
の金属化合物である。それらの金属化合物の例として、
ＺｎＣｌ4 ，ＺｎＨ2 ，Ｚｎ（ＯＣ3 Ｈ7 ）2 ，Ｚｎ
（Ｃ2 Ｈ5）2 ，Ｚｎ（Ｃ11Ｈ19Ｏ2 ）2 等が挙げられ
る。本発明における反応を例示すると、次のようなもの
が挙げられる。 ２ＺｎＣｌ4 ＋Ｏ2 → ２ＺｎＯ＋４Ｃｌ2 ＺｎＨ2 ＋Ｏ2 → ＺｎＯ＋Ｈ2 Ｏ Ｚｎ（ＯＣ3 Ｈ7 ）2 ＋Ｏ2 → ＺｎＯ＋Ｃx Ｈy Ｏ
z ＋Ｈ2 Ｏ Ｚｎ（Ｃ2 Ｈ5 ）2 ＋ Ｏ2 → ＺｎＯ＋Ｈ2 Ｏ＋Ｃ
4 Ｈ8 Ｚｎ（Ｃ11Ｈ19Ｏ2 ）2 ＋Ｏ2 → ＺｎＯ＋Ｃx Ｈy
Ｏz 上記の式において、Ｃx Ｈy Ｏz は生成有機物の構造が
不明であるため、一般式で表したものである。ｘ、ｙ、
及びｚは、０又は任意の正の整数である。Next, the method for producing zinc oxide ultrafine particles of the present invention using such an apparatus will be described. The metal compound containing zinc as a raw material is a metal compound such as a chloride, a hydride, an alkoxide, an alkyl compound, or a β-diketone compound. As examples of those metal compounds,
ZnCl 4 , ZnH 2 , Zn (OC 3 H 7 ) 2 , Zn
(C 2 H 5) 2, Zn (C 11 H 19 O 2) 2 and the like. Examples of the reaction in the present invention include the following. 2ZnCl 4 + O 2 → 2ZnO + 4Cl 2 ZnH 2 + O 2 → ZnO + H 2 O Zn (OC 3 H 7 ) 2 + O 2 → ZnO + C x H y O
z + H 2 O Zn (C 2 H 5 ) 2 + O 2 → ZnO + H 2 O + C
4 H 8 Zn (C 11 H 19 O 2 ) 2 + O 2 → ZnO + C x H y
O z In the above formula, C x H y O z is represented by the general formula because the structure of the produced organic substance is unknown. x, y,
And z are 0 or any positive integer.
【００１４】本発明における熱分解反応とは、亜鉛を含
む金属化合物が熱エネルギーを受けて、亜鉛原子または
酸化亜鉛分子に近い状態まで分解される反応のことであ
り、また酸化反応とは、その亜鉛原子または酸化亜鉛分
子に近い状態まで分解されたものが酸素との接触酸化反
応により、酸素格子欠陥が少なく、結晶性の高い酸化亜
鉛分子となる反応のことをいう。The thermal decomposition reaction in the present invention is a reaction in which a metal compound containing zinc is decomposed by receiving thermal energy to a state close to a zinc atom or a zinc oxide molecule, and the oxidation reaction is It is a reaction in which a substance decomposed to a state close to a zinc atom or a zinc oxide molecule becomes a zinc oxide molecule having high oxygen crystallinity and a small amount of oxygen lattice defects by a catalytic oxidation reaction with oxygen.
【００１５】キャリアーガスとは、不活性ガス、あるい
は熱分解反応及び酸化反応の進行を妨げないガスを言
い、例えばヘリウム、空気、窒素等が用いられる。本発
明では、酸素を含むキャリアーガスを用いるが、その酸
素ガス濃度は、亜鉛を含む金属化合物中の亜鉛原子のモ
ル数以上に、酸素原子のモル数を与えられる様に、キャ
リアーガス中の酸素濃度を一定量に調整するのが好まし
い。また、キャリアーガスの流量は反応器内における原
料ガス及び酸素を含むキャリアーガスの滞留時間が１秒
より短くならないようにキャリアーガスの流量を調節す
るのが好ましい。The carrier gas is an inert gas or a gas that does not hinder the progress of the thermal decomposition reaction and the oxidation reaction, and for example, helium, air, nitrogen or the like is used. In the present invention, a carrier gas containing oxygen is used, and the oxygen gas concentration thereof is equal to or higher than the number of moles of zinc atoms in the metal compound containing zinc so that the number of moles of oxygen atoms is given to oxygen in the carrier gas. It is preferable to adjust the concentration to a constant amount. Further, the flow rate of the carrier gas is preferably adjusted so that the residence time of the raw material gas and the carrier gas containing oxygen in the reactor does not become shorter than 1 second.
【００１６】原料ガス濃度は、キャリアーガスに対し
て、０．００１〜４０重量％の範囲で、望ましくは０．
０１〜２０重量％の範囲が良い。その理由は、原料ガス
濃度が０．００１重量％より小さい場合、微粒子の生成
量が極めて少なくなり、また原料ガス濃度が４０重量％
より大きい場合、原料ガス分子同士の凝集やそれらの反
応器壁への沈着が激しく起こり、生成微粒子の大きさが
不均一となり、その歩留まりが悪くなるからである。加
熱体を有する反応器内の温度分布としては均一であるも
のが好ましい。例えば、反応器が円筒型であれば、半径
方向及び軸方向において、温度分布が均一であることが
好ましい。反応器内の圧力は、特に限定されないが、Ｃ
ＶＤ法における微粒子生成を考えた場合、常圧付近にす
ることが好ましい。The raw material gas concentration is in the range of 0.001 to 40% by weight, preferably 0.
The range of 01 to 20% by weight is preferable. The reason is that when the source gas concentration is less than 0.001% by weight, the amount of fine particles produced is extremely small, and the source gas concentration is 40% by weight.
If it is larger, the agglomeration of the source gas molecules with each other and their deposition on the reactor wall occur violently, the size of the produced fine particles becomes non-uniform, and the yield deteriorates. It is preferable that the temperature distribution in the reactor having the heating element is uniform. For example, if the reactor is a cylindrical type, it is preferable that the temperature distribution is uniform in the radial direction and the axial direction. The pressure in the reactor is not particularly limited, but C
Considering the generation of fine particles in the VD method, it is preferable that the pressure is around normal pressure.
【００１７】本発明により得られる酸化亜鉛超微粒子
は、単分散性が良く、微粒子表面も清浄であり、また原
料ガス濃度または反応器内におけるガスの滞留時間の調
整により、０．００５〜０．２μｍの範囲のものが得ら
れる。なかでも、微粒化による機能の向上を考慮した場
合、０．０１〜０．１５μｍの範囲が好ましく、０．０
１〜０．１０μｍの範囲が更に好ましい。尚、酸化亜鉛
超微粒子の粒子径は、種々の方法で測定できるが、例え
ば走査型または透過型電子顕微鏡により測定できる。The zinc oxide ultrafine particles obtained according to the present invention have good monodispersity, the surface of the fine particles is clean, and 0.005 to 0.50% by adjusting the concentration of the raw material gas or the residence time of the gas in the reactor. A range of 2 μm is obtained. Especially, considering the improvement of the function due to atomization, the range of 0.01 to 0.15 μm is preferable, and
The range of 1 to 0.10 μm is more preferable. The particle size of the zinc oxide ultrafine particles can be measured by various methods, for example, a scanning type or transmission electron microscope.
【００１８】本発明の酸化亜鉛超微粒子は、実質的に球
状である。この球状を表わす指標として球形度を用いて
表現することができる。球形度とは、粒子と同じ体積を
有する球の表面積を粒子の表面積で割った値をさすが、
不規則粒子の表面積は測定しにくいので、本発明におい
ては実用球形度として以下の式を用いる。 実用球形度＝（粒子の体積／外接球の体積)1/3 即ち、本発明でいう球形度とは、前述の実用球形度をさ
すが、本発明では実用球形度が０．８以上のものを実質
的に球状という。本発明の酸化亜鉛超微粒子の比表面積
は、平均の比表面積が７０〜３００ｍ2 ／ｇである。こ
のように比表面積が高い為に、触媒効果も極めて高いと
言える。尚、比表面積は窒素の吸着量よりＢＥＴ法を用
いて測定することができる。The zinc oxide ultrafine particles of the present invention are substantially spherical. It can be expressed by using sphericity as an index representing this spherical shape. The sphericity refers to the value obtained by dividing the surface area of a sphere having the same volume as the particle by the surface area of the particle,
Since the surface area of irregular particles is difficult to measure, the following formula is used as the practical sphericity in the present invention. Practical sphericity = (volume of particles / volume of circumscribing sphere) 1/3 That is, the sphericity referred to in the present invention refers to the above-mentioned practical sphericity, but in the present invention, the practical sphericity is 0.8 or more. Substantially spherical. The average specific surface area of the zinc oxide ultrafine particles of the present invention is 70 to 300 m 2 / g. It can be said that the catalytic effect is extremely high because of the high specific surface area. The specific surface area can be measured by the BET method from the adsorption amount of nitrogen.
【００１９】本発明の酸化亜鉛超微粒子は、平均粒子径
が０．００５〜０．２μｍの範囲のものが得られるが、
この粒子径領域では可視光域（４００〜８００ｎｍ）の
光波長に比べて十分に小さい為に光透過性が高く、すな
わち透明性が極めて高いと言える。即ち、可視光分光分
析において、光路長１ｍｍ、グリセリン水溶液中（グリ
セリンと水の重量比は９：１）での酸化亜鉛超微粒子の
懸濁濃度を０．１重量％として光透過率の測定を行なっ
たとき、光波長８００ｎｍ及び／又は光波長４００ｎｍ
における光透過率がそれぞれ９０％以上、４０％以上で
ある。また、紫外線域（紫外線Ｂ域は光波長２９０〜３
２０ｎｍ、紫外線Ａ域は光波長３２０〜４００ｎｍ）に
おいては、前述の粒子径領域は無視できない大きさとな
るので、この紫外線領域では光散乱の為に光透過性が低
くなり、また酸化亜鉛の励起子吸収端が紫外線Ａ域内に
あるので、光吸収も起こると言える。即ち、同様にして
紫外線分光分析を行った場合、光波長３５０ｎｍ及び／
又は３００ｎｍにおける光透過率は２％以下である。従
って、光波長が４００ｎｍ、８００ｎｍにおける光透過
率より、可視光域における透明性が評価でき、また光波
長が３５０ｎｍ及び／又は３００ｎｍにおける光透過率
より、紫外線域における遮蔽性が評価できる。The zinc oxide ultrafine particles of the present invention have an average particle size in the range of 0.005 to 0.2 μm.
In this particle size region, the light transmittance is high, that is, the transparency is extremely high because it is sufficiently smaller than the light wavelength in the visible light region (400 to 800 nm). That is, in the visible light spectroscopic analysis, the light transmittance was measured with an optical path length of 1 mm and a suspension concentration of ultrafine zinc oxide particles in an aqueous glycerin solution (the weight ratio of glycerin and water was 9: 1) was 0.1% by weight. When performed, the light wavelength is 800 nm and / or the light wavelength is 400 nm
The light transmittances in the above are 90% or more and 40% or more, respectively. In the ultraviolet range (UV B range is light wavelength 290 to 3
In the wavelength range of 20 nm and ultraviolet A region (light wavelength 320 to 400 nm), the above-mentioned particle size region becomes a size that cannot be ignored, and therefore light transmittance is low in this ultraviolet region due to light scattering, and excitons of zinc oxide are also present. Since the absorption edge is in the ultraviolet region A, it can be said that light absorption also occurs. That is, when ultraviolet spectroscopic analysis is performed in the same manner, the light wavelength is 350 nm and /
Alternatively, the light transmittance at 300 nm is 2% or less. Therefore, the transparency in the visible light region can be evaluated by the light transmittance at the light wavelengths of 400 nm and 800 nm, and the shielding property in the ultraviolet region can be evaluated by the light transmittance at the light wavelength of 350 nm and / or 300 nm.
【００２０】[0020]
【実施例】本発明を実施例および比較例を用いて説明す
るが、本発明はこれらの実施例のみに限定されるもので
はない。 実施例１ 図１に示す反応装置を用いて、酸化亜鉛超微粒子の製造
を行なった。ジピバロイルメタナート亜鉛（Ｚｎ（Ｃ11
Ｈ19Ｏ2 ）2 ）を、蒸発器により１１５℃にて気化さ
せ、流量を２Ｌ／ｍｉｎに制御された窒素及び空気の混
合キャリアーガス（窒素ガスと空気ガスとの混合体積比
は１：１）を用いて、加熱炉により８００℃に温度制御
された反応管（セラミックス製、内径３０ｍｍ、外径４
０ｍｍ、長さ５０ｃｍ）に送り、反応管内部で、ジピバ
ロイルメタナート亜鉛の熱分解反応及び酸化反応によ
り、酸化亜鉛超微粒子を生成させ、気固混相の状態で得
られる酸化亜鉛超微粒子を反応管出口直後に取り付けた
拡散荷電型静電捕集器により回収した。尚、この時の原
料ガス濃度は、原料の蒸発量を重量法を用いて測定する
ことにより、窒素及び空気の混合キャリアーガスに対し
て５．５重量％、また反応器内でのガスの平均滞留時間
は約１１秒である。EXAMPLES The present invention will be described with reference to examples and comparative examples, but the present invention is not limited to these examples. Example 1 Zinc oxide ultrafine particles were produced using the reaction apparatus shown in FIG. Dipivaloylmethanate zinc (Zn (C 11
H 19 O 2 ) 2 ) is vaporized by an evaporator at 115 ° C., and a mixed carrier gas of nitrogen and air whose flow rate is controlled to 2 L / min (mixing volume ratio of nitrogen gas and air gas is 1: 1). ), A reaction tube whose temperature is controlled to 800 ° C. by a heating furnace (ceramic, inner diameter 30 mm, outer diameter 4
0 mm, 50 cm in length), and inside the reaction tube, zinc dipivaloylmethanate zinc pyrolysis reaction and oxidation reaction to produce zinc oxide ultrafine particles, which are obtained in a gas-solid mixed phase state. Was collected by a diffusion charge type electrostatic collector attached immediately after the reaction tube outlet. The concentration of the raw material gas at this time is 5.5% by weight with respect to the mixed carrier gas of nitrogen and air by measuring the evaporation amount of the raw material using a gravimetric method, and the average of the gas in the reactor. The residence time is about 11 seconds.
【００２１】上記条件により得られた酸化亜鉛超微粒子
は、実用球形度が０．９２の実質的に球状の微粒子であ
り、その結晶相はウルツ鉱型であり、その粒子径は平均
径（個数基準）で約０．０６μｍであり、その粒子径分
布は、０．０１〜０．０３μｍが８％、０．０３〜０．
０６μｍが４５％、０．０６〜０．０９μｍが４０％、
０．０９〜０．１２μｍが７％であった。捕集した酸化
亜鉛超微粒子の収率（重量比）は、８１％であった。ま
た、平均の比表面積値は２００ｍ2 ／ｇであった。尚、
生成した酸化亜鉛超微粒子の結晶相はＸ線回折装置によ
り測定し、また、粒子径は走査型電子顕微鏡を用いて測
定し、平均の比表面積値はＢＥＴ式比表面積計を用い
た。以下、実施例２〜４、比較例１でも、同様の方法で
測定を行なった。The zinc oxide ultrafine particles obtained under the above conditions are substantially spherical fine particles having a practical sphericity of 0.92, the crystal phase thereof is wurtzite type, and the particle diameter thereof is the average diameter (number of particles). The standard particle size distribution is about 0.06 μm, and the particle size distribution thereof is 0.01% to 0.03 μm, 8%, 0.03 to 0.
45% for 06 μm, 40% for 0.06 to 0.09 μm,
0.09 to 0.12 μm was 7%. The yield (weight ratio) of the collected zinc oxide ultrafine particles was 81%. The average specific surface area value was 200 m 2 / g. still,
The crystal phase of the produced zinc oxide ultrafine particles was measured by an X-ray diffractometer, the particle size was measured by a scanning electron microscope, and the average specific surface area value was measured by a BET type specific surface area meter. Hereinafter, also in Examples 2 to 4 and Comparative Example 1, measurement was performed by the same method.
【００２２】次に、得られた酸化亜鉛超微粒子につい
て、紫外線・可視光分光光度計を用いて、光波長２００
〜８００ｎｍにおける光透過率の測定を行った。その測
定結果を図２に示す。測定条件を、石英ガラスセル（光
路長１ｍｍ）、グリセリン水溶液中（グリセリンと水の
重量比は９：１）での酸化亜鉛超微粒子の懸濁濃度を0.
１重量％とした。図２より、可視光域（λ＝４００〜８
００ｎｍ）における光透過率Ｔ＝４７〜９３％（λが４
００ｎｍでのＴが４７％、λが８００ｎｍでのＴが９３
％であることを表わす。以下、同様にして表示する。）
であり、また紫外線Ｂ、Ａ域（λ＝２９０〜４００ｎ
ｍ）における光透過率Ｔ＝０〜４７％、特にλ＝３００
〜３５０ｎｍでの光透過率Ｔ＝０〜０．５％であった。
従って、本実施例により生成した酸化亜鉛超微粒子は可
視光域における透明性が非常に良く、かつ紫外線域にお
ける遮蔽性も極めて良いと言える。Next, the obtained zinc oxide ultrafine particles were measured with an ultraviolet / visible light spectrophotometer at an optical wavelength of 200.
The light transmittance at -800 nm was measured. The measurement result is shown in FIG. The measurement conditions were a quartz glass cell (optical path length 1 mm) and a suspension concentration of ultrafine zinc oxide particles in an aqueous glycerin solution (weight ratio of glycerin to water was 9: 1).
It was set to 1% by weight. From FIG. 2, the visible light region (λ = 400 to 8)
Light transmittance T = 47 to 93% (where λ is 4
T at 00 nm is 47%, T at λ is 800 nm is 93
Indicates that it is%. Hereinafter, it is similarly displayed. )
And the ultraviolet rays B and A range (λ = 290 to 400n
m) light transmittance T = 0 to 47%, especially λ = 300
The light transmittance T at 350 nm was T = 0 to 0.5%.
Therefore, it can be said that the zinc oxide ultrafine particles produced in this example have very good transparency in the visible light region and very good shielding property in the ultraviolet light region.
【００２３】実施例２ 亜鉛アルコキシド（Ｚｎ（ＯＣ3 Ｈ7 ）2 ）を、蒸発器
により５０℃にて気化させ、流量を１Ｌ／ｍｉｎに制御
された窒素及び空気の混合キャリアーガス（窒素ガスと
空気ガスとの混合体積比は１：１）を用いて、加熱炉に
より６００℃に温度制御された反応管（実施例１で用い
た反応管と同じ）に送り、反応管内部で、亜鉛アルコキ
シドの熱分解反応及び酸化反応により、酸化亜鉛超微粒
子を生成させ、気固混相の状態で得られる酸化亜鉛超微
粒子を反応管出口直後に取り付けた拡散荷電型静電捕集
器により回収した。尚、この時の原料ガス濃度は、原料
の蒸発量を重量法を用いて測定することにより、窒素及
び空気の混合キャリアーガスに対して９．５重量％、ま
た反応器内でのガスの平均滞留時間は約２２秒である。Example 2 Zinc alkoxide (Zn (OC 3 H 7 ) 2 ) was vaporized by an evaporator at 50 ° C., and a mixed carrier gas of nitrogen and air (a nitrogen gas and a nitrogen gas were controlled at a flow rate of 1 L / min). Using a mixing volume ratio with air gas of 1: 1), the mixture was sent to a reaction tube whose temperature was controlled at 600 ° C. by a heating furnace (the same as the reaction tube used in Example 1), and the zinc alkoxide was introduced inside the reaction tube. Zinc oxide ultrafine particles were generated by the thermal decomposition reaction and oxidation reaction of 1. and the zinc oxide ultrafine particles obtained in a gas-solid mixed phase were collected by a diffusion charge type electrostatic collector attached immediately after the outlet of the reaction tube. The concentration of the raw material gas at this time is 9.5% by weight based on the mixed carrier gas of nitrogen and air by measuring the evaporation amount of the raw material using a gravimetric method, and the average of the gas in the reactor. The residence time is about 22 seconds.
【００２４】上記条件により得られた酸化亜鉛超微粒子
は、実用球形度が０．９０の実質的に球状の微粒子であ
り、その結晶相はウルツ鉱型であり、その粒子径は平均
径（個数基準）で約０．０９μｍであり、その粒子径分
布は、０．０１〜０．０３μｍが２％、０．０３〜０．
０６μｍが３％、０．０６〜０．０９μｍが４４％、
０．０９〜０．１２μｍが５１％であった。捕集した酸
化亜鉛超微粒子の収率（重量比）は、８０％であった。
また、平均の比表面積値は１３３ｍ2 ／ｇであった。The zinc oxide ultrafine particles obtained under the above conditions are substantially spherical fine particles having a practical sphericity of 0.90, the crystal phase thereof is wurtzite type, and the particle diameter thereof is the average diameter (number of particles). The standard particle size distribution is about 0.09 μm, and the particle size distribution thereof is 0.01% to 0.03 μm, 2%, 0.03 to 0.
06 μm is 3%, 0.06 to 0.09 μm is 44%,
51% was 0.09 to 0.12 μm. The yield (weight ratio) of the collected zinc oxide ultrafine particles was 80%.
The average specific surface area value was 133 m 2 / g.
【００２５】次に、得られた酸化亜鉛超微粒子につい
て、紫外線・可視光分光光度計を用いて、光波長２００
〜８００ｎｍにおける光透過率の測定を行った。その測
定結果を図３に示す。測定条件は実施例１と同じく、石
英ガラスセル（光路長１ｍｍ）、グリセリン水溶液中
（グリセリンと水の重量比は９：１）での酸化亜鉛超微
粒子の懸濁濃度を０．１重量％とした。図３より、可視
光域（λ＝４００〜８００ｎｍ）における光透過率Ｔ＝
４５〜９２％であり、また紫外線Ｂ、Ａ域（λ＝２９０
〜４００ｎｍ）における光透過率Ｔ＝０〜４５％、特に
λ＝３００〜３５０ｎｍでの光透過率Ｔ＝０〜１％であ
った。従って、本実施例により生成した酸化亜鉛超微粒
子は可視光域における透明性が非常に良く、かつ紫外線
域における遮蔽性も極めて良いと言える。Next, the obtained zinc oxide ultrafine particles were measured with an ultraviolet / visible light spectrophotometer at an optical wavelength of 200.
The light transmittance at -800 nm was measured. The measurement result is shown in FIG. The measurement conditions were the same as in Example 1, except that the suspension concentration of the zinc oxide ultrafine particles in the silica glass cell (optical path length 1 mm) and the aqueous glycerin solution (the weight ratio of glycerin and water was 9: 1) was 0.1% by weight. did. From FIG. 3, the light transmittance T = in the visible light range (λ = 400 to 800 nm)
45 to 92%, and ultraviolet B and A regions (λ = 290
Light transmittance T = 0 to 45% at ˜400 nm), and particularly light transmittance T = 0 to 1% at λ = 300 to 350 nm. Therefore, it can be said that the zinc oxide ultrafine particles produced in this example have very good transparency in the visible light region and very good shielding property in the ultraviolet light region.
【００２６】実施例３ ジエチル亜鉛（Ｚｎ（Ｃ2 Ｈ5 ）2 ）を、蒸発器により
４５℃にて気化させ、流量を２Ｌ／ｍｉｎに制御された
窒素及び空気の混合キャリアーガス（窒素ガスと空気ガ
スとの混合体積比は１：１）を用いて、加熱炉により５
００℃に温度制御された反応管（実施例１で用いた反応
管に同じ）に送り、反応管内部で、ジエチル亜鉛の熱分
解反応及び酸化反応により、酸化亜鉛超微粒子を生成さ
せ、気固混相の状態で得られる酸化亜鉛超微粒子を反応
管出口直後に取り付けた拡散荷電型静電捕集器により回
収した。尚、この時の原料ガス濃度は、原料の蒸発量を
重量法を用いて測定することにより、窒素及び空気の混
合キャリアーガスに対して２．６重量％、また反応器内
でのガスの平均滞留時間は約１１秒である。Example 3 Diethyl zinc (Zn (C 2 H 5 ) 2 ) was vaporized at 45 ° C. by an evaporator, and a mixed carrier gas of nitrogen and air (a nitrogen gas and a nitrogen gas were controlled at a flow rate of 2 L / min). The volume ratio with air gas is 1: 1)
It is sent to a reaction tube whose temperature is controlled at 00 ° C (the same as the reaction tube used in Example 1), and zinc oxide ultrafine particles are generated by a thermal decomposition reaction and an oxidation reaction of diethylzinc inside the reaction tube, and gas solidification is performed. The zinc oxide ultrafine particles obtained in the mixed phase were collected by a diffusion charge type electrostatic collector installed immediately after the outlet of the reaction tube. The concentration of the raw material gas at this time is 2.6% by weight with respect to the mixed carrier gas of nitrogen and air by measuring the evaporation amount of the raw material using a gravimetric method, and the average of the gas in the reactor. The residence time is about 11 seconds.
【００２７】上記条件により得られた酸化亜鉛超微粒子
は、実用球形度が０．９３の実質的に球状の微粒子であ
り、その結晶相は、ウルツ鉱型であり、その粒子径は平
均径（個数基準）で約０．０１μｍであり、その粒子径
分布は、０．００５〜０．００８μｍが１％、０．００
８〜０．０１μｍが４７％、０．０１〜０．０１２μｍ
が４６％、０．０１２〜０．０１５μｍが６％であっ
た。捕集した酸化亜鉛超微粒子の収率（重量比）は、８
０％であった。また、平均の比表面積値は２８７ｍ2 ／
ｇであった。The zinc oxide ultrafine particles obtained under the above conditions are substantially spherical fine particles having a practical sphericity of 0.93, the crystal phase thereof is wurtzite type, and the particle diameter thereof is the average diameter ( (Number basis) is about 0.01 μm, and the particle size distribution is 0.005 to 0.008 μm, 1%, 0.00
8% to 0.01 μm is 47%, 0.01 to 0.012 μm
Was 46% and 0.012 to 0.015 μm was 6%. The yield (weight ratio) of the collected ultrafine zinc oxide particles was 8
It was 0%. The average specific surface area value is 287 m 2 /
It was g.
【００２８】次に、得られた酸化亜鉛超微粒子につい
て、紫外線・可視光分光光度計を用いて、光波長２００
〜８００ｎｍにおける光透過率の測定を行った。その測
定結果を図４に示す。測定条件は実施例１と同じく、石
英ガラスセル（光路長１ｍｍ）、グリセリン水溶液中
（グリセリンと水の重量比は９：１）での酸化亜鉛超微
粒子の懸濁濃度を０．１重量％とした。図４より、可視
光域（λ＝４００〜８００ｎｍ）における光透過率Ｔ＝
５３〜９７％であり、また紫外線Ｂ、Ａ域（λ＝２９０
〜４００ｎｍ）における光透過率Ｔ＝０〜５３％、特に
λ＝３００〜３５０ｎｍでの光透過率Ｔ＝０〜０．２％
であった。従って、本実施例により生成した酸化亜鉛超
微粒子は可視光域における透明性が非常に良く、かつ紫
外線域における遮蔽性も極めて良いと言える。Next, the obtained zinc oxide ultrafine particles were measured with an ultraviolet / visible light spectrophotometer at an optical wavelength of 200.
The light transmittance at -800 nm was measured. The measurement result is shown in FIG. The measurement conditions were the same as in Example 1, except that the suspension concentration of the zinc oxide ultrafine particles in the silica glass cell (optical path length 1 mm) and the aqueous glycerin solution (the weight ratio of glycerin and water was 9: 1) was 0.1% by weight. did. From FIG. 4, the light transmittance T = in the visible light range (λ = 400 to 800 nm)
53 to 97%, and ultraviolet B and A regions (λ = 290
Light transmittance T = 0 to 53%, especially light transmittance T = 0 to 0.2% at λ = 300 to 350 nm.
Met. Therefore, it can be said that the zinc oxide ultrafine particles produced in this example have very good transparency in the visible light region and very good shielding property in the ultraviolet light region.
【００２９】実施例４ 塩化亜鉛（ＺｎＣｌ4 ）を、蒸発器により５５℃にて気
化させ、流量を１Ｌ／ｍｉｎに制御された窒素及び空気
の混合キャリアーガス（窒素ガスと空気ガスとの混合体
積比は１：１）を用いて、加熱炉により７００℃に温度
制御された反応管（実施例１で用いた反応管に同じ）に
送り、反応管内部で、塩化亜鉛の熱分解反応及び酸化反
応により、酸化亜鉛超微粒子を生成させ、気固混相の状
態で得られる酸化亜鉛超微粒子を反応管出口直後に取り
付けた拡散荷電型静電捕集器により回収した。尚、この
時の原料ガス濃度は、原料の蒸発量を重量法を用いて測
定することにより、窒素及び空気の混合キャリアーガス
に対して１５重量％、また反応器内でのガスの平均滞留
時間は約２２秒である。Example 4 Zinc chloride (ZnCl 4 ) was vaporized by an evaporator at 55 ° C., and a mixed carrier gas of nitrogen and air (mixed volume of nitrogen gas and air gas was controlled at a flow rate of 1 L / min). The ratio of 1: 1 was used to send to a reaction tube whose temperature was controlled at 700 ° C. by a heating furnace (the same as the reaction tube used in Example 1), and inside the reaction tube, a thermal decomposition reaction and oxidation of zinc chloride were carried out. Zinc oxide ultrafine particles were generated by the reaction, and the zinc oxide ultrafine particles obtained in a gas-solid mixed phase were recovered by a diffusion charge type electrostatic collector attached immediately after the reaction tube outlet. The concentration of the raw material gas at this time is 15% by weight with respect to the mixed carrier gas of nitrogen and air by measuring the evaporation amount of the raw material using a gravimetric method, and the average residence time of the gas in the reactor. Is about 22 seconds.
【００３０】上記条件により得られた酸化亜鉛超微粒子
は、実用球形度が０．９１の実質的に球状の微粒子であ
り、その結晶相は、ウルツ鉱型であり、その粒子径は平
均径（個数基準）で約０．１５μｍであり、その粒子径
分布は、０．０６〜０．０９μｍが３％、０．０９〜
０．１２μｍが５％、０．１２〜０．１５μｍが４２
％、０．１５〜０．１８μｍが４６％、０．１８〜０．
２０μｍが４％であった。捕集した酸化亜鉛超微粒子の
収率（重量比）は、７９％であった。また、平均の比表
面積値は８０ｍ2 ／ｇであった。The zinc oxide ultrafine particles obtained under the above conditions are substantially spherical fine particles having a practical sphericity of 0.91, the crystal phase thereof is wurtzite type, and the particle diameter thereof is the average diameter ( (Number basis) is about 0.15 μm, and the particle size distribution is 0.06 to 0.09 μm, 3%, 0.09 to
0.12 μm is 5%, 0.12-0.15 μm is 42
%, 0.15 to 0.18 μm is 46%, 0.18 to 0.
20 μm was 4%. The yield (weight ratio) of the collected zinc oxide ultrafine particles was 79%. The average specific surface area value was 80 m 2 / g.
【００３１】次に、得られた酸化亜鉛超微粒子につい
て、紫外線・可視光分光光度計を用いて、光波長２００
〜８００ｎｍにおける光透過率の測定を行った。その測
定結果を図５に示す。測定条件は実施例１と同じく、石
英ガラスセル（光路長１ｍｍ）、グリセリン水溶液中
（グリセリンと水の重量比は９：１）での酸化亜鉛超微
粒子の懸濁濃度を０．１重量％とした。図５より、可視
光域（λ＝４００〜８００ｎｍ）における光透過率Ｔ＝
４２〜９０％であり、また紫外線Ｂ、Ａ域（λ＝２９０
〜４００ｎｍ）における光透過率Ｔ＝０〜４２％、特に
λ＝３００〜３５０ｎｍでの光透過率Ｔ＝０〜２％であ
った。従って、本実施例により生成した酸化亜鉛超微粒
子は可視光域における透明性が非常に良く、かつ紫外線
域における遮蔽性も極めて良いと言える。Next, the obtained zinc oxide ultrafine particles were measured at an optical wavelength of 200 using an ultraviolet / visible light spectrophotometer.
The light transmittance at -800 nm was measured. The measurement result is shown in FIG. The measurement conditions were the same as in Example 1, except that the suspension concentration of the zinc oxide ultrafine particles in the silica glass cell (optical path length 1 mm) and the aqueous glycerin solution (the weight ratio of glycerin and water was 9: 1) was 0.1% by weight. did. From FIG. 5, the light transmittance T = in the visible light range (λ = 400 to 800 nm)
42 to 90%, and ultraviolet B and A regions (λ = 290
The light transmittance T = 0 to 42% at (.about.400 nm), particularly the light transmittance T = 0 to 2% at λ = 300 to 350 nm. Therefore, it can be said that the zinc oxide ultrafine particles produced in this example have very good transparency in the visible light region and very good shielding property in the ultraviolet light region.
【００３２】比較例１ フランス法により製造された市販品の酸化亜鉛微粒子
（微粒品、三井金属鉱業製）について、実施例１、２と
同様の検討を行った。この酸化亜鉛微粒子は、その結晶
相はウルツ鉱型であり、その粒子径は平均径（個数基
準）で約０．２５μｍであり、その粒子径分布は、０．
１６〜０．１９μｍが１％、０．１９〜０．２２μｍが
２％、０．２２〜０．２５μｍが４７％、０．２５〜
０．２８μｍが５０％であった。また、平均の比表面積
値は９０ｍ2 ／ｇであった。Comparative Example 1 With respect to commercially available zinc oxide fine particles (fine particles, manufactured by Mitsui Mining & Smelting Co., Ltd.) manufactured by the French method, the same examination as in Examples 1 and 2 was conducted. The zinc oxide fine particles have a wurtzite type crystal phase, a particle diameter of about 0.25 μm in average diameter (number basis), and a particle diameter distribution of 0.
16-0.19 μm is 1%, 0.19-0.22 μm is 2%, 0.22-0.25 μm is 47%, 0.25-0.25
0.28 μm was 50%. The average specific surface area value was 90 m 2 / g.
【００３３】次に、上記の酸化亜鉛微粒子について、紫
外線・可視光分光光度計を用いて、光波長２００〜８０
０ｎｍにおける光透過率の測定を行った。その測定結果
を図６に示す。測定条件は実施例１と同じく、石英ガラ
スセル（光路長１ｍｍ）、グリセリン水溶液中（グリセ
リンと水の重量比は９：１）での酸化亜鉛超微粒子の懸
濁濃度を０．１重量％とした。図６より、可視光域（λ
＝４００〜８００ｎｍ）における光透過率Ｔ＝４５〜８
５％であり、また紫外線Ｂ、Ａ域（λ＝２９０〜４００
ｎｍ）における光透過率Ｔ＝３１〜４５％、特にλ＝３
００〜３５０ｎｍでの光透過率Ｔ＝３２〜３３％であっ
た。従って、この酸化亜鉛微粒子は可視光域における透
明性は実施例１〜４の場合より悪く、紫外線域における
遮蔽性も非常に悪いと言える。これは、実施例１〜４の
場合と比較して、フランス法による生成粒子径が大きい
為に、波長の短い紫外線域の光が通過し易く、紫外線域
における遮蔽性が低下したと考えられる。Next, with respect to the above zinc oxide fine particles, a light wavelength of 200 to 80 was measured by using an ultraviolet / visible light spectrophotometer.
The light transmittance at 0 nm was measured. The measurement result is shown in FIG. The measurement conditions were the same as in Example 1, except that the suspension concentration of the zinc oxide ultrafine particles in the silica glass cell (optical path length 1 mm) and the aqueous glycerin solution (the weight ratio of glycerin and water was 9: 1) was 0.1% by weight. did. From Fig. 6, visible light range (λ
= 400 to 800 nm) light transmittance T = 45 to 8
5%, and ultraviolet B and A regions (λ = 290 to 400)
nm) light transmittance T = 31 to 45%, especially λ = 3
The light transmittance T at 00 to 350 nm was 32 to 33%. Therefore, it can be said that the zinc oxide fine particles have a poorer transparency in the visible light range than those in Examples 1 to 4 and a very poor shielding property in the ultraviolet range. It is considered that this is because, as compared with the cases of Examples 1 to 4, since the particle size generated by the French method is large, light in the ultraviolet region having a short wavelength easily passes therethrough and the shielding property in the ultraviolet region is deteriorated.
【００３４】[0034]
【発明の効果】本発明によれば、平均粒子径が０．００
５〜０．２μｍであって、実質的に球状である酸化亜鉛
超微粒子を、亜鉛を含む金属化合物を気化させ原料ガス
とし、該原料ガスを酸素を含むキャリアーガスを用いて
高温の反応管へ導入し、該反応管内部で該原料ガスを熱
分解反応及び酸化反応させるという簡便な方法により、
連続して安価に製造できる。また、本発明による酸化亜
鉛超微粒子は、可視光域における透明性が非常に高く、
紫外線Ｂ，Ａ領域における遮蔽性も極めて高い。According to the present invention, the average particle size is 0.00
Substantially spherical zinc oxide ultrafine particles having a particle size of 5 to 0.2 μm are vaporized from a metal compound containing zinc to form a raw material gas, and the raw material gas is transferred to a high temperature reaction tube using a carrier gas containing oxygen. By a simple method of introducing and causing the raw material gas to undergo a thermal decomposition reaction and an oxidation reaction inside the reaction tube,
It can be manufactured continuously at low cost. Further, the zinc oxide ultrafine particles according to the present invention have very high transparency in the visible light region,
The shielding property in the ultraviolet B and A regions is also extremely high.
【図１】本発明における微粒子製造装置の一例を示す概
略図である。FIG. 1 is a schematic view showing an example of a fine particle production apparatus according to the present invention.
【図２】実施例１の酸化亜鉛超微粒子の紫外線・可視光
分光分析による光透過率の測定結果を表わすチャート図
である。FIG. 2 is a chart showing the measurement results of light transmittance of ultrafine zinc oxide particles of Example 1 by ultraviolet / visible light spectroscopic analysis.
【図３】実施例２の酸化亜鉛超微粒子の紫外線・可視光
分光分析による光透過率の測定結果を表わすチャート図
である。FIG. 3 is a chart showing the result of measurement of light transmittance of ultrafine zinc oxide particles of Example 2 by ultraviolet / visible light spectroscopic analysis.
【図４】実施例３の酸化亜鉛超微粒子の紫外線・可視光
分光分析による光透過率の測定結果を表わすチャート図
である。FIG. 4 is a chart showing the results of measurement of light transmittance of ultrafine zinc oxide particles of Example 3 by ultraviolet / visible light spectroscopic analysis.
【図５】実施例４の酸化亜鉛超微粒子の紫外線・可視光
分光分析による光透過率の測定結果を表わすチャート図
である。FIG. 5 is a chart showing the measurement results of light transmittance of ultrafine zinc oxide particles of Example 4 by ultraviolet / visible light spectroscopic analysis.
【図６】比較例１の酸化亜鉛微粒子の紫外線・可視光分
光分析による光透過率の測定結果を表わすチャート図で
ある。FIG. 6 is a chart showing the measurement results of light transmittance of the zinc oxide fine particles of Comparative Example 1 by ultraviolet / visible light spectroscopic analysis.
１ 原料気化装置 ２ キャリアーガス供給装置 ３ 加熱体 ４ 反応管 ５ 生成超微粒子の捕集装置 1 raw material vaporizer 2 carrier gas supply device 3 heating body 4 reaction tube 5 collection device for generated ultrafine particles
Claims (8)
スとし、該原料ガスを酸素を含むキャリアーガスを用い
て高温の反応管へ導入し、該反応管内部で該原料ガスを
熱分解反応及び酸化反応させることにより得られる、平
均粒子径が０．００５〜０．２μｍであって実質的に球
状である酸化亜鉛超微粒子。1. A metal compound containing zinc is vaporized into a raw material gas, the raw material gas is introduced into a high temperature reaction tube using a carrier gas containing oxygen, and the raw material gas is pyrolyzed and reacted inside the reaction tube. Zinc oxide ultrafine particles having an average particle size of 0.005 to 0.2 μm and having a substantially spherical shape, which are obtained by an oxidation reaction.
０〜３００ｍ2 ／ｇである請求項１記載の酸化亜鉛超微
粒子。2. The zinc oxide ultrafine particles have an average specific surface area of 7
The zinc oxide ultrafine particles according to claim 1, which are 0 to 300 m 2 / g.
ｍ、グリセリン水溶液中（グリセリンと水の重量比は
９：１）での酸化亜鉛超微粒子の懸濁濃度を０．１重量
％として光透過率の測定を行なったとき、光波長８００
ｎｍ及び／又は光波長４００ｎｍにおける光透過率がそ
れぞれ９０％以上、４０％以上であることを特徴とする
請求項１又は２記載の酸化亜鉛超微粒子。3. An optical path length of 1 m in visible light spectroscopic analysis.
When the light transmittance was measured with the suspension concentration of the zinc oxide ultrafine particles in an aqueous glycerin solution (the weight ratio of glycerin and water was 9: 1) as 0.1% by weight,
nm and / or light wavelength 400 nm has a light transmittance of 90% or more and 40% or more, respectively, and the zinc oxide ultrafine particles according to claim 1 or 2.
ｍ、グリセリン水溶液中（グリセリンと水の重量比は
９：１）での酸化亜鉛超微粒子の懸濁濃度を０．１重量
％として光透過率の測定を行なったとき、光波長３５０
ｎｍ及び／又は３００ｎｍにおける光透過率が２％以下
であることを特徴とする請求項３記載の酸化亜鉛超微粒
子。4. An optical path length of 1 m in ultraviolet spectroscopic analysis.
m, when the light transmittance was measured with a suspension concentration of zinc oxide ultrafine particles in an aqueous glycerin solution (the weight ratio of glycerin and water was 9: 1) as 0.1% by weight, a light wavelength of 350
4. The zinc oxide ultrafine particles according to claim 3, which have a light transmittance of 2% or less at nm and / or 300 nm.
スとし、該原料ガスを酸素を含むキャリアーガスを用い
て高温の反応管へ導入し、該反応管内部で該原料ガスを
熱分解反応及び酸化反応させることにより、平均粒子径
が０．００５〜０．２μｍであって実質的に球状である
酸化亜鉛超微粒子を連続的に製造することを特徴とする
酸化亜鉛超微粒子の製造方法。5. A metal compound containing zinc is vaporized into a raw material gas, the raw material gas is introduced into a high-temperature reaction tube using a carrier gas containing oxygen, and the raw material gas is pyrolyzed and reacted inside the reaction tube. A method for producing zinc oxide ultrafine particles, characterized by continuously producing zinc oxide ultrafine particles having an average particle size of 0.005 to 0.2 μm and having a substantially spherical shape by an oxidation reaction.
０〜３００ｍ2 ／ｇである請求項５記載の製造方法。6. The average specific surface area of zinc oxide ultrafine particles is 7.
The production method according to claim 5, which is 0 to 300 m 2 / g.
ｍ、グリセリン水溶液中（グリセリンと水の重量比は
９：１）での酸化亜鉛超微粒子の懸濁濃度を０．１重量
％として光透過率の測定を行なったとき、光波長８００
ｎｍ及び／又は光波長４００ｎｍにおける光透過率がそ
れぞれ９０％以上、４０％以上であることを特徴とする
請求項５又は６記載の製造方法。7. An optical path length of 1 m in visible light spectroscopic analysis.
When the light transmittance was measured with the suspension concentration of the zinc oxide ultrafine particles in an aqueous glycerin solution (the weight ratio of glycerin and water was 9: 1) as 0.1% by weight,
7. The manufacturing method according to claim 5, wherein the light transmittance at 90 nm and / or the light wavelength at 400 nm is 90% or more and 40% or more, respectively.
ｍ、グリセリン水溶液中（グリセリンと水の重量比は
９：１）での酸化亜鉛超微粒子の懸濁濃度を０．１重量
％として光透過率の測定を行なったとき、光波長３５０
ｎｍ及び／又は３００ｎｍにおける光透過率が２％以下
であることを特徴とする請求項７記載の製造方法。8. An optical path length of 1 m in ultraviolet spectroscopic analysis.
m, when the light transmittance was measured with a suspension concentration of zinc oxide ultrafine particles in an aqueous glycerin solution (the weight ratio of glycerin and water was 9: 1) as 0.1% by weight, a light wavelength of 350
The light transmittance in nm and / or 300 nm is 2% or less, The manufacturing method of Claim 7 characterized by the above-mentioned.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19312893A JPH0725614A (en) | 1993-07-07 | 1993-07-07 | Ultrafine zinc oxide particle and production thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19312893A JPH0725614A (en) | 1993-07-07 | 1993-07-07 | Ultrafine zinc oxide particle and production thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0725614A true JPH0725614A (en) | 1995-01-27 |
Family
ID=16302738
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP19312893A Pending JPH0725614A (en) | 1993-07-07 | 1993-07-07 | Ultrafine zinc oxide particle and production thereof |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0725614A (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01126205A (en) * | 1987-07-06 | 1989-05-18 | Sumitomo Electric Ind Ltd | Superconducting thin film and its formation |
| EP0786982A4 (en) * | 1993-04-28 | 1997-08-06 | ||
| WO2000046152A1 (en) * | 1999-02-05 | 2000-08-10 | Showa Denko K.K. | Ultra-fine particles of zinc oxide, method for preparing the same and cosmetic comprising the same |
| JP2003052800A (en) * | 2001-08-21 | 2003-02-25 | Toagosei Co Ltd | Deodorant composition suitable for deodorization of sulfur-base malodor |
| JP2006527160A (en) * | 2003-06-11 | 2006-11-30 | インペリアル・ケミカル・インダストリーズ・ピーエルシー | Zinc oxide |
| JP2007503373A (en) * | 2003-08-22 | 2007-02-22 | デグサ アクチエンゲゼルシャフト | Surface modified zinc oxide |
| EP2218685A1 (en) * | 2009-02-16 | 2010-08-18 | Süd-Chemie AG | Zinc oxide crystal particle and method for its production |
| WO2012169611A1 (en) * | 2011-06-10 | 2012-12-13 | 堺化学工業株式会社 | Rounded zinc peroxide particles, rounded zinc oxide particles, manufacturing method therefor, cosmetic material, and heat-dissipating filler |
-
1993
- 1993-07-07 JP JP19312893A patent/JPH0725614A/en active Pending
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01126205A (en) * | 1987-07-06 | 1989-05-18 | Sumitomo Electric Ind Ltd | Superconducting thin film and its formation |
| EP0786982A4 (en) * | 1993-04-28 | 1997-08-06 | ||
| EP0786982A1 (en) * | 1993-04-28 | 1997-08-06 | Sunsmart, Inc. | Topical ultra-violet radiation protectants |
| JP4462523B2 (en) * | 1999-02-05 | 2010-05-12 | 昭和電工株式会社 | Ultrafine zinc oxide, method for producing the same, and cosmetics using the same |
| WO2000046152A1 (en) * | 1999-02-05 | 2000-08-10 | Showa Denko K.K. | Ultra-fine particles of zinc oxide, method for preparing the same and cosmetic comprising the same |
| AU765502B2 (en) * | 1999-02-05 | 2003-09-18 | Showa Denko Kabushiki Kaisha | Ultra-fine particles of zinc oxide, method for preparing the same and cosmetic comprising the same |
| JP2003052800A (en) * | 2001-08-21 | 2003-02-25 | Toagosei Co Ltd | Deodorant composition suitable for deodorization of sulfur-base malodor |
| JP2006527160A (en) * | 2003-06-11 | 2006-11-30 | インペリアル・ケミカル・インダストリーズ・ピーエルシー | Zinc oxide |
| JP4709142B2 (en) * | 2003-06-11 | 2011-06-22 | クローダ インターナショナル パブリック リミティド カンパニー | Zinc oxide |
| JP2007503373A (en) * | 2003-08-22 | 2007-02-22 | デグサ アクチエンゲゼルシャフト | Surface modified zinc oxide |
| EP2218685A1 (en) * | 2009-02-16 | 2010-08-18 | Süd-Chemie AG | Zinc oxide crystal particle and method for its production |
| WO2012169611A1 (en) * | 2011-06-10 | 2012-12-13 | 堺化学工業株式会社 | Rounded zinc peroxide particles, rounded zinc oxide particles, manufacturing method therefor, cosmetic material, and heat-dissipating filler |
| JPWO2012169611A1 (en) * | 2011-06-10 | 2015-02-23 | 堺化学工業株式会社 | Round zinc peroxide particles, round zinc oxide particles, production methods thereof, cosmetics and heat dissipating fillers |
| US9376319B2 (en) | 2011-06-10 | 2016-06-28 | Sakai Chemical Industry Co., Ltd. | Rounded zinc peroxide particles, rounded zinc oxide particles, method for production thereof, cosmetic and heat releasing filler |
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