JPH0524882A - Silica-titania particle having high transparency and production thereof - Google Patents
Silica-titania particle having high transparency and production thereofInfo
- Publication number
- JPH0524882A JPH0524882A JP20339891A JP20339891A JPH0524882A JP H0524882 A JPH0524882 A JP H0524882A JP 20339891 A JP20339891 A JP 20339891A JP 20339891 A JP20339891 A JP 20339891A JP H0524882 A JPH0524882 A JP H0524882A
- Authority
- JP
- Japan
- Prior art keywords
- silica
- refractive index
- titania
- particles
- titania particles
- 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.)
- Granted
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B19/00—Other methods of shaping glass
- C03B19/10—Forming beads
- C03B19/1005—Forming solid beads
- C03B19/106—Forming solid beads by chemical vapour deposition; by liquid phase reaction
- C03B19/1065—Forming solid beads by chemical vapour deposition; by liquid phase reaction by liquid phase reactions, e.g. by means of a gel phase
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2201/00—Type of glass produced
- C03B2201/06—Doped silica-based glasses
- C03B2201/30—Doped silica-based glasses doped with metals, e.g. Ga, Sn, Sb, Pb or Bi
- C03B2201/40—Doped silica-based glasses doped with metals, e.g. Ga, Sn, Sb, Pb or Bi doped with transition metals other than rare earth metals, e.g. Zr, Nb, Ta or Zn
- C03B2201/42—Doped silica-based glasses doped with metals, e.g. Ga, Sn, Sb, Pb or Bi doped with transition metals other than rare earth metals, e.g. Zr, Nb, Ta or Zn doped with titanium
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、ＬＥＤなどの光機能デ
バイス封止用モールディングコンパウンドの充填材等と
して好適に使用される透明性の高いシリカ−チタニア粒
子及びその製造方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to highly transparent silica-titania particles suitable for use as a filler for molding compounds for encapsulating optical functional devices such as LEDs, and a method for producing the same.
【０００２】[0002]
【従来の技術】現在、ＬＥＤ，ＬＤ，ＣＣＤ，フォトダ
イオード，フォトカプラーのような光機能デバイスは、
主としてセラミックパッケージや透明プラスチックで封
止されているが、これらのデバイス用の新規な封止材料
として、充填材をエポキシ樹脂に充填させたエポキシモ
ールディングコンパウンドが要望されている。2. Description of the Related Art Currently, optical functional devices such as LEDs, LDs, CCDs, photodiodes and photocouplers are
Although it is mainly sealed with a ceramic package or transparent plastic, an epoxy molding compound in which a filler is filled with an epoxy resin is desired as a new sealing material for these devices.
【０００３】かかる充填材としては、光透過率が高いこ
とが必要であるばかりでなく、光散乱による透過率の低
下を防ぐため、屈折率がエポキシ樹脂の屈折率と同等程
度であることが必要で、このように高光透過率並びにエ
ポキシ樹脂と同等の屈折率という特性を兼ね備えた充填
材を透明エポキシ樹脂に配合することにより、透明性に
優れたエポキシモールディングコンパウンドを得ること
が可能である。The filler is required not only to have a high light transmittance, but also to have a refractive index similar to that of the epoxy resin in order to prevent a decrease in transmittance due to light scattering. It is possible to obtain an epoxy molding compound having excellent transparency by blending a transparent epoxy resin with a filler having such characteristics as high light transmittance and a refractive index equivalent to that of an epoxy resin.
【０００４】本発明者らは、既に、特願平２−２８０７
７号等において、上記の充填材として好適に使用されう
る高透明性シリカ−チタニア粒子及びその製造方法につ
いて提案した。そして、かかる高透明性シリカ−チタニ
ア粒子を透明エポキシ樹脂に充填して、透明性に優れた
エポキシモールディングコンパウンドを得ている。The present inventors have already filed Japanese Patent Application No. 2-2807.
No. 7, etc., proposed highly transparent silica-titania particles which can be preferably used as the above-mentioned filler and a method for producing the same. Then, the highly transparent silica-titania particles are filled in a transparent epoxy resin to obtain an epoxy molding compound having excellent transparency.
【０００５】[0005]
【発明が解決しようとする課題】しかし、本発明者ら
が、上記特願平２−２８０７７号等に従って、屈折率
（ｎD）が１．４６〜１．５８の広い範囲にわたって高
透明性シリカ−チタニア粒子の製造を試みたところ、屈
折率（ｎD）が１．４６から１．５０未満及び１．５３
から１．５８の範囲では、確実に高透明なシリカ−チタ
ニア粒子が得られるが、屈折率（ｎD）が１．５０以上
１．５３未満の範囲では、シリカ−チタニア粒子にアナ
ターゼ（Ａｎａｔａｓｅ）微結晶が析出し、高透明なも
のは得難いものであった。However, according to the above-mentioned Japanese Patent Application No. 2-28077, the present inventors have proposed a highly transparent silica over a wide range of refractive index (n D ) of 1.46 to 1.58. - was tried the preparation of titania particles, the refractive index (n D) is less than 1.46 1.50 and 1.53
In the range of 1.58 to 1.58, highly transparent silica-titania particles can be reliably obtained, but in the range of the refractive index (n D ) of 1.50 or more and less than 1.53, the silica-titania particles are anatase (Anatase). It was difficult to obtain highly transparent ones in which fine crystals were precipitated.
【０００６】このように、微結晶が析出した透過率値の
低いシリカ−チタニア粒子は、上述した光機能デバイス
用エポキシモールディングコンパウンドの充填材には使
用し難いものである。As described above, silica-titania particles having a low transmittance value in which fine crystals are deposited are difficult to use as a filler for the epoxy molding compound for optical functional devices described above.
【０００７】従って、シリカ−チタニア粒子を用いて透
明性に優れたエポキシモールディングコンパウンドを得
るためには、当該屈折率（ｎD）の範囲を避ける必要が
あり、このため使用されるエポキシ樹脂の種類，組成が
制限されていた。Therefore, in order to obtain an epoxy molding compound having excellent transparency by using silica-titania particles, it is necessary to avoid the range of the refractive index (n D ), and therefore the type of epoxy resin used. ， The composition was limited.
【０００８】本発明は上記事情に鑑みなされたもので、
屈折率（ｎD）が１．５０以上１．５３未満の範囲にお
いても光透過率が高く、光機能デバイス用エポキシモー
ルディングコンパウンドの充填材として好適に使用する
ことができるシリカ−チタニア粒子及びその製造方法を
提供することを目的とする。The present invention has been made in view of the above circumstances.
Silica-titania particles having high light transmittance even in a range of refractive index (n D ) of 1.50 or more and less than 1.53, which can be suitably used as a filler for an epoxy molding compound for optical functional devices, and production thereof. The purpose is to provide a method.
【０００９】[0009]
【課題を解決するための手段及び作用】本発明者らは、
上記目的を達成するため鋭意検討を重ねた結果、シリコ
ンアルコキシドとチタンアルコキシドとを加水分解，重
縮合して得られるシリカ−チタニアゾルをゲル化，乾燥
し、次いでこの乾燥ゲルを所定粒度に粉砕し、焼結ガラ
ス化してシリカ−チタニア粒子を製造する方法におい
て、下記式（３）
Ｓｉ（ＯＲ1）4 …（３）
（但し、Ｒ1は炭素数１〜４のアルキル基である。）
で示されるシリコンアルコキシドを酸性水溶液で反応さ
せた部分加水分解物と下記式（４）
Ｔｉ（ＯＲ2）4 …（４）
（但し、Ｒ2は炭素数１〜４のアルキル基である。）
で示されるチタンアルコキシドとの部分縮合物を、更に
酸性水溶液で加水分解，重縮合反応させることにより、
屈折率（ｎD）が１．５０以上１．５３未満であって
も、下記直線透過率測定方法Ａによる９００ｎｍ〜６０
０ｎｍの波長範囲での直線透過率が６０％以上である高
透明性シリカ−チタニア粒子が得られることを知見し
た。Means and Actions for Solving the Problems The present inventors have
As a result of repeated intensive studies to achieve the above object, hydrolysis of silicon alkoxide and titanium alkoxide, silica-titania sol obtained by polycondensation is gelled and dried, and then this dried gel is pulverized to a predetermined particle size, In the method of producing silica-titania particles by sintering and vitrification, the following formula (3) Si (OR 1 ) 4 (3) (wherein R 1 is an alkyl group having 1 to 4 carbon atoms) is shown. And a partial hydrolyzate obtained by reacting a silicon alkoxide with an acidic aqueous solution represented by the following formula (4) Ti (OR 2 ) 4 (4) (wherein R 2 is an alkyl group having 1 to 4 carbon atoms). The partial condensate with the titanium alkoxide is further hydrolyzed and polycondensed with an acidic aqueous solution,
Even if the refractive index (n D ) is 1.50 or more and less than 1.53, 900 nm to 60 according to the following linear transmittance measuring method A
It has been found that highly transparent silica-titania particles having a linear transmittance of 60% or more in the wavelength range of 0 nm can be obtained.
【００１０】Ａ：下記の一般式（１）で示されるビスフ
ェノール型エポキシ樹脂又は下記の一般式（２）で示さ
れるノボラック型エポキシ樹脂とグリシジルエーテル類
から選ばれる１種又は２種以上とを混合し、シリカ−チ
タニア粒子との屈折率差が±０．０００５以内になる溶
液を調製する。この溶液と平均粒径５〜３０μｍに粉砕
されたシリカ−チタニア粒子とを重量比で１：１に混合
し、その混合物について１ｍｍの光路長で直線透過率を
測定する。A: A bisphenol type epoxy resin represented by the following general formula (1) or a novolac type epoxy resin represented by the following general formula (2) is mixed with one kind or two or more kinds selected from glycidyl ethers. Then, a solution in which the difference in refractive index from the silica-titania particles is within ± 0.0005 is prepared. This solution and silica-titania particles crushed to an average particle size of 5 to 30 μm are mixed in a weight ratio of 1: 1 and the linear transmittance of the mixture is measured with an optical path length of 1 mm.
【００１１】[0011]
【化２】 [Chemical 2]
【００１２】即ち、本発明者らが提案した特願平２−２
８０７７号のシリカ−チタニア粒子の製造方法などで
は、シリコンアルコキシドを酸性水溶液で反応させた部
分加水分解物とチタンアルコキシドとを反応させた部分
縮合物を更に水で加水分解，重縮合していたが、かかる
方法では屈折率（ｎD）が１．５０以上１．５３未満の
範囲において、高透明なシリカ−チタニア粒子は得られ
難いものであった。That is, Japanese Patent Application No. 2-2 proposed by the present inventors.
In the method of producing silica-titania particles of No. 8077, a partial hydrolyzate obtained by reacting a silicon alkoxide with an acidic aqueous solution and a partial condensate obtained by reacting a titanium alkoxide were further hydrolyzed and polycondensed. With such a method, it was difficult to obtain highly transparent silica-titania particles in the range where the refractive index (n D ) is 1.50 or more and less than 1.53.
【００１３】しかし、本発明者らは、シリコンアルコキ
シドを酸性水溶液で反応させた部分加水分解物とチタン
アルコキシドとを反応させた部分縮合物を、更に水では
なく酸性水溶液で加水分解，重縮合反応させることによ
り、屈折率（ｎD）が１．５０以上１．５３未満の範囲
でも上述した試験方法Ａによる９００ｎｍ〜６００ｎｍ
の波長範囲での直線透過率が６０％以上と高透明で、ア
ナターゼ微結晶が析出しないシリカ−チタニア粒子を最
終的に得ることができることを見い出した。However, the inventors of the present invention further hydrolyzed a partial condensate obtained by reacting a partial hydrolyzate obtained by reacting a silicon alkoxide with an acidic aqueous solution with a titanium alkoxide by an acidic aqueous solution instead of water, and carrying out a polycondensation reaction. As a result, the refractive index (n D ) is 900 nm to 600 nm according to the above-mentioned test method A even in the range of 1.50 or more and less than 1.53.
It was found that the silica-titania particles having a high linear transparency in the wavelength range of 60% or more and having no anatase crystallites can be finally obtained.
【００１４】この理由として、シリコンアルコキシドを
酸性水溶液で反応させた部分加水分解物とチタンアルコ
キシドとを反応させた部分縮合物中には、チタンアルコ
キシドのモノマーが多量に存在しており、従って、従来
製法では、次の加水分解，重縮合工程においてチタンア
ルコキシドの縮合反応速度が非常に速いため、ＴｉＯ2
のブロックが形成されて後の焼結工程で微結晶が生成し
やすくなるが、これに対して、本発明のように酸性水溶
液で前記の加水分解、重縮合反応を行なった場合には、
チタンアルコキシドの縮合反応速度を充分低く抑えるこ
とができるため、以下の３種の縮合反応をより均一に起
こさせることができたものと考えられる。The reason for this is that a large amount of the titanium alkoxide monomer is present in the partial hydrolyzate obtained by reacting the silicon alkoxide with the acidic aqueous solution and the partial condensate obtained by reacting the titanium alkoxide, and therefore, the conventional method. the method, following hydrolysis, for very fast condensation reaction rate of the titanium alkoxide in the polycondensation step, TiO 2
The block is formed and microcrystals are likely to be generated in the subsequent sintering step. On the other hand, when the hydrolysis or polycondensation reaction is performed in an acidic aqueous solution as in the present invention,
It is considered that since the condensation reaction rate of the titanium alkoxide can be suppressed to a sufficiently low level, the following three kinds of condensation reactions could be caused to occur more uniformly.
【００１５】[0015]
【化３】 [Chemical 3]
【００１６】従って、本発明は、屈折率（ｎD）が１．
５０以上１．５３未満であって、上記直線透過率測定方
法Ａによる９００ｎｍ〜６００ｎｍの波長範囲での直線
透過率が６０％以上である高透明性シリカ−チタニア粒
子、及びシリコンアルコキシドとチタンアルコキシドと
を加水分解，重縮合して得られるシリカ−チタニアゾル
をゲル化，乾燥し、次いでこの乾燥ゲルを所定粒度に粉
砕し、焼結ガラス化してシリカ−チタニア粒子を製造す
る方法において、下記式（３）
Ｓｉ（ＯＲ1）4 …（３）
（但し、Ｒ1は炭素数１〜４のアルキル基である。）
で示されるシリコンアルコキシドを酸性水溶液で反応さ
せた部分加水分解物と下記式（４）
Ｔｉ（ＯＲ2）4 …（４）
（但し、Ｒ2は炭素数１〜４のアルキル基である。）
で示されるチタンアルコキシドとの部分縮合物を、更に
酸性水溶液で加水分解，重縮合反応させて、シリカチタ
ニアゾルを得ることを特徴とする、屈折率（ｎD）が
１．５０以上１．５３未満の高透明性シリカ−チタニア
粒子の製造方法を提供する。Therefore, according to the present invention, the refractive index (n D ) is 1.
Highly transparent silica-titania particles having a linear transmittance of 50% or more and less than 1.53 and having a linear transmittance of 60% or more in the wavelength range of 900 nm to 600 nm according to the linear transmittance measuring method A, and a silicon alkoxide and a titanium alkoxide. The silica-titania sol obtained by hydrolyzing and polycondensing is gelled and dried, and then the dried gel is pulverized to a predetermined particle size and sintered and vitrified to produce silica-titania particles. ) Si (OR 1 ) 4 (3) (wherein R 1 is an alkyl group having 1 to 4 carbon atoms) is partially hydrolyzed with a silicon alkoxide represented by the following formula (4) ) Ti (OR 2 ) 4 (4) (wherein R 2 is an alkyl group having 1 to 4 carbon atoms), a partial condensate with a titanium alkoxide is further added to an acidic aqueous solution. A method for producing highly transparent silica-titania particles having a refractive index (n D ) of 1.50 or more and less than 1.53, which is characterized in that a silica-titania sol is obtained by hydrolysis and polycondensation reaction.
【００１７】以下、本発明につき更に詳述すると、本発
明に係る高透明性シリカ−チタニア粒子を得る場合、ま
ず出発原料としてシリコンアルコキシドとチタンアルコ
キシドとを用いる。The present invention will be described in more detail below. To obtain the highly transparent silica-titania particles according to the present invention, silicon alkoxide and titanium alkoxide are first used as starting materials.
【００１８】ここで、シリコンアルコキシドとしては下
記式（３）
Ｓｉ（ＯＲ1）4 …（３）
（但し、 Ｒ1は炭素数１〜４のアルキル基である。）
のものが用いられ、例えばＳｉ（ＯＣＨ3）4、Ｓｉ（Ｏ
Ｃ2Ｈ5）4などが挙げられる。Here, as the silicon alkoxide,
Expression (3)
Si (OR1)Four … (3)
(However, R1Is an alkyl group having 1 to 4 carbon atoms. )
The one used is, for example, Si (OCH3)Four, Si (O
C2HFive)FourAnd so on.
【００１９】一方、チタンアルコキシドとしては下記式
（４）
Ｔｉ（ＯＲ2）4 …（４）
（但し、 Ｒ2は炭素数１〜４のアルキル基である。）
のものが用いられ、例えばＴｉ（Ｏ−ｉｓｏ−Ｃ3Ｈ7）
4、Ｔｉ（Ｏ−ｎ−Ｃ4Ｈ9）4などが挙げられる。On the other hand, the titanium alkoxide has the following formula
(4)
Ti (OR2)Four … (4)
(However, R2Is an alkyl group having 1 to 4 carbon atoms. )
Used are, for example, Ti (O-iso-C3H7)
Four, Ti (O-n-CFourH9)FourAnd so on.
【００２０】この場合、ＴｉＯ2をＳｉＯ2とＴｉＯ2と
の合計に対して８〜１２モル％となるような量でシリコ
ンアルコキシドとチタンアルコキシドとを用いることが
好ましく、これにより屈折率（ｎD）が１．５０以上
１．５３未満の範囲になるシリカ−チタニア粒子を最終
的に得ることができる。[0020] In this case, it is preferable to use a silicon alkoxide and a titanium alkoxide in an amount such that 8 to 12 mol% of TiO 2 with respect to the total of SiO 2 and TiO 2, thereby the refractive index (n D It is possible to finally obtain silica-titania particles in which) is in the range of 1.50 or more and less than 1.53.
【００２１】これらの原料からゾルを得る方法として
は、上記シリコンアルコキシドを希釈用の溶媒としての
メタノール，エタノール，プロパノールなどのようなア
ルコールに溶解し、これに酸触媒を含む理論量以下の水
を加えて、シリコンアルコキシドを部分的に加水分解し
たものにチタンアルコキシドを添加して部分的に縮合さ
せ、更に水を追加してシリカ−チタニアゾルを調製する
方法が好適に採用されるる。As a method for obtaining a sol from these raw materials, the above silicon alkoxide is dissolved in an alcohol such as methanol, ethanol, propanol, etc. as a solvent for dilution, and water below a theoretical amount containing an acid catalyst is added to this. In addition, a method of preparing a silica-titania sol by adding titanium alkoxide to a partially hydrolyzed product of silicon alkoxide to partially condense it, and further adding water thereto is preferably adopted.
【００２２】この際に、本発明のようにシリコンアルコ
キシドを酸性水溶液で反応させた部分加水分解物とチタ
ンアルコキシドとの部分縮合物を、更に酸性水溶液で加
水分解，重縮合反応させることにより、屈折率（ｎD）
が１．５０以上１．５３未満の範囲でも高透明なシリカ
−チタニア粒子を製造できる。At this time, as in the present invention, a partial condensate of a titanium alkoxide and a partial hydrolyzate obtained by reacting a silicon alkoxide with an acidic aqueous solution is further hydrolyzed and polycondensed to produce a refraction Rate (n D )
Is 1.50 or more and less than 1.53, highly transparent silica-titania particles can be produced.
【００２３】ここで、触媒として使用される酸の種類と
しては特に制限されないが、塩酸，硝酸，硫酸等の鉱
酸、または酢酸，シュウ酸等の有機酸が好適に使用され
る。The type of acid used as the catalyst is not particularly limited, but mineral acids such as hydrochloric acid, nitric acid and sulfuric acid, or organic acids such as acetic acid and oxalic acid are preferably used.
【００２４】以上のようにして生成したゾルは、ゲル化
用の容器に移し、密閉状態にしてから恒温乾燥器中に静
置させてゲル化させる方法が好適に採用される。A method in which the sol produced as described above is transferred to a container for gelation, sealed and then allowed to stand in a thermostatic dryer to gelate is preferably adopted.
【００２５】このゲル化温度及びゲル化後の熟成温度に
ついては、これを６０℃より低くするとアルコキシドの
加水分解が不完全なものとなる場合があるので、このゲ
ル化及び熟成の温度は６０℃以上とすることが好まし
い。なお、熟成はこの加水分解を完全なものとする点か
ら１時間以上、好ましくは５時間以上とすることがよ
い。Regarding the gelling temperature and the aging temperature after gelation, if the temperature is lower than 60 ° C., hydrolysis of the alkoxide may be incomplete, so the gelling and aging temperature is 60 ° C. The above is preferable. The aging is carried out for 1 hour or longer, preferably 5 hours or longer, in order to complete the hydrolysis.
【００２６】次に、上記ゲル化、熟成の終了した湿式ゲ
ルの乾燥方法としては特に制限されないが、例えばゲル
を熟成することに用いた密封容器の蓋を取り、そのまま
恒温乾燥器中に放置して乾燥し、乾燥ゲルを得る方法を
採用することができる。Next, the method for drying the wet gel after the gelation and aging is not particularly limited, but for example, the lid of the sealed container used for aging the gel is removed and left in the constant temperature oven as it is. It is possible to employ a method of obtaining a dry gel by drying by drying.
【００２７】乾燥ゲルは、次いで粉砕されるが、粉砕方
法は特に制限されず、また粒径も適宜選定され、用途に
応じた適当な粉砕方法，粒径を採用し得るが、光機能デ
バイス封止用エポキシモールディング用の充填材とする
場合は、平均粒径が１〜１００μｍ、特に５〜３０μｍ
とすることが好ましい。The dry gel is then pulverized, but the pulverization method is not particularly limited, and the particle size is appropriately selected. An appropriate pulverization method and particle size can be adopted according to the application. When used as a filler for stopping epoxy molding, the average particle size is 1 to 100 μm, particularly 5 to 30 μm.
It is preferable that
【００２８】次に、粉砕した乾燥ゲルを焼結ガラス化す
るが、焼結温度は１０５０〜１２５０℃の範囲が好まし
い。焼結温度が１０５０℃未満では粒子が完全に均一に
緻密化せず、従ってこのシリカ−チタニア粒子の透過率
を測定した場合、粒子内部に入射した光は、シリカ−チ
タニア構成粒子とその構成粒子間隙の空孔との間の屈折
率差により散乱されるため、その結果として低い透過率
値になる場合があり、また、焼結温度が１２５０℃より
も高い温度では、たとえ加水分解，重縮合反応を酸の存
在下で行なっても、アナターゼ微結晶の析出が起こるた
め、この温度範囲でも同様に光透過性に優れるシリカ−
チタニア粒子は得られない場合がある。Next, the crushed dry gel is sintered and vitrified, and the sintering temperature is preferably in the range of 1050 to 1250 ° C. When the sintering temperature is less than 1050 ° C., the particles are not completely and uniformly densified. Therefore, when the transmittance of the silica-titania particles is measured, the light incident on the inside of the particles is the silica-titania constituent particles and their constituent particles. Because of scattering due to the difference in refractive index between the voids in the gap, a low transmittance value may result as a result, and even if the sintering temperature is higher than 1250 ° C, even if hydrolysis or polycondensation occurs. Even if the reaction is carried out in the presence of an acid, since precipitation of anatase microcrystals occurs, silica-like silica having excellent light transmittance in this temperature range as well.
In some cases, titania particles cannot be obtained.
【００２９】なお、この焼結方法は、上記温度範囲内で
あればよく、特に制限されないが、電気炉等の一定温度
に保つ焼結炉を使用し、炉中に空気、酸素ガスまたは酸
素と空気との混合ガスを送入して炉内を酸化性雰囲気と
することが好ましい。また、所定の温度に達するまでの
昇温速度は通常１０〜５００℃／時とすることが好まし
い。焼結時間は上記温度範囲で通常１０〜３００分であ
る。The sintering method is not particularly limited as long as it is within the above temperature range, but a sintering furnace such as an electric furnace which is maintained at a constant temperature is used, and air, oxygen gas or oxygen is used in the furnace. It is preferable to introduce a mixed gas with air to create an oxidizing atmosphere in the furnace. Further, it is preferable that the rate of temperature increase until reaching a predetermined temperature is usually 10 to 500 ° C./hour. The sintering time is usually 10 to 300 minutes in the above temperature range.
【００３０】このようにして得られるシリカ−チタニア
粒子は、シリカ−チタニア粒子との屈折率差が±０．０
００５以内に調製された下記式（１）のビスフェノール
型エポキシ樹脂又は下記式（２）のノボラック型エポキ
シ樹脂とグリシジルエーテル類から選ばれる１種又は２
種以上とを混合した溶液と、平均粒径５〜３０μｍに粉
砕された当該シリカ−チタニア粒子とを重量比で１：１
に混合し、その混合物について１ｍｍの光路長で直線透
過率を測定した場合、９００ｎｍから６００ｎｍの波長
範囲での直線透過率が６０％以上であり、屈折率
（ｎD）が１．５０以上１．５３未満の範囲であって
も、透明性が優れている。The silica-titania particles thus obtained have a refractive index difference of ± 0.0 from that of the silica-titania particles.
1 or 2 selected from bisphenol type epoxy resin of the following formula (1) or novolac type epoxy resin of the following formula (2) and glycidyl ethers prepared within 005
1: 1 by weight ratio of the solution in which the seeds or more are mixed and the silica-titania particles crushed to an average particle size of 5 to 30 μm.
When the linear transmittance of the mixture is measured with an optical path length of 1 mm, the linear transmittance in the wavelength range of 900 nm to 600 nm is 60% or more, and the refractive index (n D ) is 1.50 or more 1. Even in the range of less than 0.53, the transparency is excellent.
【００３１】[0031]
【化４】 [Chemical 4]
【００３２】従って、本発明のシリカ−チタニア粒子
は、光機能デバイス封止用モールディングコンパウン
ド、特にエポキシ樹脂用の充填材として好適なものであ
り、透明なエポキシ樹脂と本発明のシリカ−チタニア粒
子とでモールディングコンパウンドを形成すれば、１ｍ
ｍ厚で光透過率が６０％以上と高透明なモールディング
コンパウンドが確実に得られるものである。Therefore, the silica-titania particles of the present invention are suitable as a molding compound for encapsulating optical functional devices, especially as a filler for epoxy resins, and include a transparent epoxy resin and the silica-titania particles of the present invention. Forming a molding compound with 1m
A highly transparent molding compound having a thickness of m and a light transmittance of 60% or more can be reliably obtained.
【００３３】また、特願平２−２８０７７号等の発明に
係るシリカ−チタニア粒子と併せて、屈折率（ｎD）が
１．４６〜１．５８の広い範囲にわたり高透明性シリカ
−チタニア粒子を製造することができるため、ほとんど
すべての種類の透明エポキシ樹脂が使用でき、透明性に
優れるエポキシモールディングコンパウンドを得ること
ができる。In addition to the silica-titania particles according to the invention of Japanese Patent Application No. 2-28077, etc., the highly transparent silica-titania particles have a refractive index (n D ) of 1.46 to 1.58 over a wide range. Since almost all kinds of transparent epoxy resins can be used, it is possible to obtain an epoxy molding compound having excellent transparency.
【００３４】[0034]
【実施例】以下、実施例と比較例を示し、本発明を具体
的に示すが、本発明は下記の実施例に制限されるもので
はない。EXAMPLES Hereinafter, the present invention will be specifically shown by showing Examples and Comparative Examples, but the present invention is not limited to the following Examples.
【００３５】〔実施例１〕正珪酸メチル（多摩化学工業
製）１５２２．２ｇとメタノール（和光純薬，特級）３
２０．４ｇとの溶液に、３０℃で０．２規定塩酸水溶液
１８０．０ｇを添加し、１時間撹拌した。そこにチタン
テトラブトキシド（日曹製）３６７．７ｇとメタノール
１６０．２ｇとの溶液を徐々に添加したのち、さらに１
時間撹拌した。その後、０．２規定塩酸水溶液６１７．
８ｇを添加し、さらに１０分間撹拌した。得られたシリ
カ−チタニアゾルをポリプロピレン製容器に入れ、６０
℃で密閉したところ、ゾルは約６０分後にゲル化した。
ゲルをそのまま６０℃密閉下で１７時間熟成した。その
後、容器の蓋を除き、９０℃の乾燥器で４日間乾燥して
乾燥ゲル体を得た。[Example 1] 1522.2 g of methyl orthosilicate (manufactured by Tama Chemical Industry) and methanol (Wako Pure Chemical Industries, special grade) 3
To a solution of 20.4 g, 180.0 g of 0.2N hydrochloric acid aqueous solution was added at 30 ° C., and the mixture was stirred for 1 hour. A solution of 367.7 g of titanium tetrabutoxide (manufactured by Nisso) and 160.2 g of methanol was gradually added thereto, and then 1
Stir for hours. Then, 0.2N hydrochloric acid aqueous solution 617.
8 g was added and stirred for another 10 minutes. The resulting silica-titania sol was placed in a polypropylene container and
When closed at 0 ° C., the sol gelled after about 60 minutes.
The gel was aged for 17 hours under the sealed condition of 60 ° C. Then, the lid of the container was removed, and the product was dried in a dryer at 90 ° C. for 4 days to obtain a dry gel body.
【００３６】この乾燥ゲル体のうち２５０ｇを容量２リ
ットルのアルミナ製ボールミルで４時間粉砕した。この
粉砕後の乾燥ゲル体を箱型電気炉に入れ、窒素１．５ｍ
3／ｈの条件で５００℃まで５時間で昇温した後、乾燥
空気１．８ｍ3／ｈの条件で１１５０℃まで８時間で昇
温し、次いで３０分間，１１５０℃に保持し、平均粒径
１１．８μｍのシリカ−チタニア粒子を得た。250 g of this dried gel was pulverized for 4 hours in a ball mill made of alumina having a capacity of 2 liters. The dry gel body after this pulverization was put into a box-type electric furnace, and 1.5 m of nitrogen was added.
After raising the temperature to 500 ° C for 5 hours under the condition of 3 / h, the temperature was raised to 1150 ° C for 8 hours under the condition of dry air 1.8m 3 / h, and then kept at 1150 ° C for 30 minutes to obtain the average particle size. Silica-titania particles having a diameter of 11.8 μm were obtained.
【００３７】〔実施例２〕正珪酸メチル１５２２．２ｇ
とメタノール３２０．４ｇとの溶液に、３０℃で０．２
規定塩酸水溶液１８０．０ｇを添加し、１時間撹拌し
た。そこにチタンテトラブトキシド４０４．８ｇとメタ
ノール１６０．２ｇとの溶液を徐々に添加した後、更に
１時間撹拌した。その後、０．２規定塩酸水溶液６２
５．６ｇを添加し、さらに１０分間撹拌した。得られた
シリカ−チタニアゾルを実施例１と同様にしてゲル化，
乾燥，粉砕した。Example 2 Methyl orthosilicate 1522.2 g
And a solution of 320.4 g of methanol, 0.2 at 30 ℃
180.0 g of a normal hydrochloric acid aqueous solution was added, and the mixture was stirred for 1 hour. A solution of titanium tetrabutoxide 404.8 g and methanol 160.2 g was gradually added thereto, and the mixture was further stirred for 1 hour. After that, 0.2N hydrochloric acid aqueous solution 62
5.6g was added and stirred for another 10 minutes. The obtained silica-titania sol was gelled in the same manner as in Example 1,
Dried and crushed.
【００３８】この粉砕後の乾燥ゲル体を箱型電気炉に入
れ、窒素１．５ｍ3／ｈの条件で５００℃まで５時間で
昇温した後、乾燥空気１．８ｍ3／ｈの条件で１１００
℃まで８時間で昇温し、次いで３０分間，１１００℃に
保持し、平均粒径１０．２μｍのシリカ−チタニア粒子
を得た。The dried gel body after the pulverization was placed in a box-type electric furnace and heated to 500 ° C. for 5 hours under the condition of 1.5 m 3 / h of nitrogen, and then under the condition of 1.8 m 3 / h of dry air. 1100
The temperature was raised to 8 ° C. in 8 hours and then kept at 1100 ° C. for 30 minutes to obtain silica-titania particles having an average particle size of 10.2 μm.
【００３９】〔比較例１〕正珪酸メチル１５２２．２ｇ
とメタノール３２０．４ｇとの溶液に、３０℃で０．２
規定塩酸水溶液１８０．０ｇを添加し、１時間撹拌し
た。そこにチタンテトラブトキシド３６７．７ｇとメタ
ノール１６０．２ｇとの溶液を徐々に添加した後、更に
１時間撹拌した。その後、純水６１７．８ｇを添加し、
更に１０分間撹拌した。得られたシリカ−チタニアゾル
を実施例１と同様にしてゲル化，乾燥，粉砕した。Comparative Example 1 Methyl orthosilicate 1522.2 g
And a solution of 320.4 g of methanol, 0.2 at 30 ℃
180.0 g of a normal hydrochloric acid aqueous solution was added, and the mixture was stirred for 1 hour. A solution of titanium tetrabutoxide (367.7 g) and methanol (160.2 g) was gradually added thereto, and the mixture was further stirred for 1 hour. Then, 617.8 g of pure water was added,
Stir for a further 10 minutes. The obtained silica-titania sol was gelled, dried and pulverized in the same manner as in Example 1.
【００４０】この粉砕後の乾燥ゲル体を箱型電気炉に入
れ、窒素１．５ｍ3／ｈの条件で５００℃まで５時間で
昇温した後、乾燥空気１．８ｍ3／ｈの条件で１１００
℃まで８時間で昇温し、次いで３０分間，１１００℃に
保持し、平均粒径９．２μｍのシリカ−チタニア粒子を
得た。The dried gel body after crushing was put in a box-type electric furnace and heated to 500 ° C. for 5 hours under the condition of 1.5 m 3 / h of nitrogen, and then under the condition of 1.8 m 3 / h of dry air. 1100
The temperature was raised to 8 ° C. in 8 hours and then kept at 1100 ° C. for 30 minutes to obtain silica-titania particles having an average particle size of 9.2 μm.
【００４１】〔比較例２〕正珪酸メチル１５２２．２ｇ
とメタノール３２０．４ｇとの溶液に、３０℃で０．２
規定塩酸水溶液１８０．０ｇを添加し、１時間撹拌し
た。そこにチタンテトラブトキシド３６７．７ｇとメタ
ノール１６０．２ｇとの溶液を徐々に添加した後、更に
１時間撹拌した。その後、純水６１７．８ｇを添加し、
更に１０分間撹拌した。得られたシリカ−チタニアゾル
を実施例１と同様にしてゲル化，乾燥，粉砕した。Comparative Example 2 Methyl orthosilicate 1522.2 g
And a solution of 320.4 g of methanol, 0.2 at 30 ℃
180.0 g of a normal hydrochloric acid aqueous solution was added, and the mixture was stirred for 1 hour. A solution of titanium tetrabutoxide (367.7 g) and methanol (160.2 g) was gradually added thereto, and the mixture was further stirred for 1 hour. Then, 617.8 g of pure water was added,
Stir for a further 10 minutes. The obtained silica-titania sol was gelled, dried and pulverized in the same manner as in Example 1.
【００４２】この粉砕後の乾燥ゲル体を箱型電気炉に入
れ、窒素１．５ｍ3／ｈの条件で５００℃まで５時間で
昇温した後、乾燥空気１．８ｍ3／ｈの条件で１１００
℃まで８時間で昇温し、次いで３０分間，１１００℃に
保持し、平均粒径９．３μｍのシリカ−チタニア粒子を
得た。The dried gel body after the pulverization was placed in a box-type electric furnace and heated to 500 ° C. for 5 hours under the condition of nitrogen 1.5 m 3 / h, and then under the condition of dry air 1.8 m 3 / h. 1100
The temperature was raised to 8 ° C. in 8 hours and then kept at 1100 ° C. for 30 minutes to obtain silica-titania particles having an average particle size of 9.3 μm.
【００４３】各シリカ−チタニア粒子の光透過率の結果
及び屈折率（ｎD）を表１に示す。なお、平均粒径、屈
折率（ｎD）、並びに光透過率の測定方法は下記の通り
である。粒度分布の測定方法
試料の分散媒として、ヘキサメタリン酸ソーダの０．２
重量％水溶液を使用し、島津製遠心沈降式粒度分布測定
装置ＳＡ−ＣＰ３Ｌにて測定した。屈折率の測定方法
アタゴ社製アッベ屈折計３Ｔにて測定した。透過率の測定方法
平均粒径５〜３０μｍのシリカ−チタニア粒子と、この
ものの屈折率に±０．０００５の範囲になるように混合
比を調整した上記式（１）のエピコート８２８（油化シ
ェルエポキシ社製エポキシ樹脂）とグリシジルエーテル
としてＧＥ−１００（同前）及びフェニルグリシジルエ
ーテルとの混合液とを重量比で１：１になるように混合
する。十分に粒子を分散させた後、この混合物を１ｍｍ
の光路長を有するセルに入れ、目視で泡が観察されなく
なるまで減圧脱気を行なう。その後、分光光度計を用い
て９００ｎｍから６００ｎｍの波長範囲で透過スペクト
ルを測定する。この場合、レファランスはブランクであ
る。The results of light transmittance and the refractive index (n D ) of each silica-titania particle are shown in Table 1. The methods for measuring the average particle diameter, the refractive index (n D ) and the light transmittance are as follows. Measurement method of particle size distribution As a dispersion medium of the sample, 0.2 of sodium hexametaphosphate was used.
The weight-% aqueous solution was used, and it measured with the Shimadzu centrifugal sedimentation type particle size distribution analyzer SA-CP3L. Measurement method of refractive index It was measured by Abbe refractometer 3T manufactured by Atago. Method for Measuring Transmittance Silica-titania particles having an average particle size of 5 to 30 μm and Epicoat 828 (oil-forming shell) of the above formula (1) in which the mixing ratio is adjusted so that the refractive index of the particles is ± 0.0005 An epoxy resin manufactured by Epoxy Co., Ltd.) and a mixed solution of GE-100 (same as above) as glycidyl ether and phenylglycidyl ether are mixed at a weight ratio of 1: 1. After thoroughly dispersing the particles, add 1 mm of this mixture.
The cell is placed in a cell having an optical path length of, and degassed under reduced pressure until no bubbles are visually observed. Then, a transmission spectrum is measured in a wavelength range of 900 nm to 600 nm using a spectrophotometer. In this case, the reference is blank.
【００４４】[0044]
【表１】 [Table 1]
【００４５】[0045]
【発明の効果】以上説明したように、本発明の高透明性
シリカ−チタニア粒子は、屈折率（ｎD）が１．５０以
上１．５３未満であるにもかかわらず透明性が優れてお
り、光機能デバイスの透明エポキシモールディングコン
パウンド用の充填材等として好適に使用することができ
るものであり、本発明の高透明性シリカ−チタニア粒子
の製造方法によれば、かかる透明性に優れたシリカ−チ
タニア粒子を確実に製造できるものである。As described above, the highly transparent silica-titania particles of the present invention have excellent transparency even though the refractive index (n D ) is 1.50 or more and less than 1.53. , Which can be suitably used as a filler or the like for a transparent epoxy molding compound of an optical functional device, and according to the method for producing highly transparent silica-titania particles of the present invention, silica excellent in such transparency -Titania particles can be reliably produced.
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.5 識別記号 庁内整理番号 ＦＩ 技術表示箇所 Ｃ０３Ｃ 4/00 6971−4Ｇ Ｃ０８Ｌ 63/00 ＮＪＷ 8416−4Ｊ Ｈ０１Ｌ 23/29 23/31 ─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. 5 Identification code Internal reference number FI Technical indication C03C 4/00 6971-4G C08L 63/00 NJW 8416-4J H01L 23/29 23/31
Claims (2)
って、下記直線透過率測定方法Ａによる９００ｎｍ〜６
００ｎｍの波長範囲での直線透過率が６０％以上である
高透明性シリカ−チタニア粒子。 Ａ：下記の一般式（１）で示されるビスフェノール型エ
ポキシ樹脂又は下記の一般式（２）で示されるノボラッ
ク型エポキシ樹脂とグリシジルエーテル類から選ばれる
１種又は２種以上とを混合し、シリカ−チタニア粒子と
の屈折率差が±０．０００５以内になる溶液を調製す
る。この溶液と平均粒径が５〜３０μｍに粉砕されたシ
リカ−チタニア粒子とを重量比で１：１に混合し、その
混合物について１ｍｍの光路長で直線透過率を測定す
る。 【化１】 1. A refractive index of 1.50 or more and less than 1.53, and 900 nm to 6 according to the following linear transmittance measuring method A.
Highly transparent silica-titania particles having a linear transmittance of 60% or more in the wavelength range of 00 nm. A: A bisphenol type epoxy resin represented by the following general formula (1) or a novolak type epoxy resin represented by the following general formula (2) is mixed with one or more types selected from glycidyl ethers, and silica is used. -Prepare a solution in which the difference in refractive index from the titania particles is within ± 0.0005. This solution and silica-titania particles crushed to an average particle size of 5 to 30 μm are mixed at a weight ratio of 1: 1 and the linear transmittance of the mixture is measured with an optical path length of 1 mm. [Chemical 1]
シドとを加水分解，重縮合して得られるシリカ−チタニ
アゾルをゲル化，乾燥し、次いでこの乾燥ゲルを所定粒
度に粉砕し、焼結ガラス化してシリカ−チタニア粒子を
製造する方法において、下記式（３） Ｓｉ（ＯＲ1）4 …（３） （但し、Ｒ1は炭素数１〜４のアルキル基である。） で示されるシリコンアルコキシドを酸性水溶液で反応さ
せた部分加水分解物と下記式（４） Ｔｉ（ＯＲ2）4 …（４） （但し、Ｒ2は炭素数１〜４のアルキル基である。） で示されるチタンアルコキシドとの部分縮合物を、更に
酸性水溶液で加水分解，重縮合反応させて、シリカチタ
ニアゾルを得ることを特徴とする請求項１記載の屈折率
が１．５０以上１．５３未満の高透明性シリカ−チタニ
ア粒子の製造方法。2. A silica-titania sol obtained by hydrolyzing and polycondensing a silicon alkoxide and a titanium alkoxide is gelated and dried, and then this dried gel is pulverized to a predetermined particle size and sintered into glass to obtain silica-titania. In the method for producing particles, a silicon alkoxide represented by the following formula (3) Si (OR 1 ) 4 (3) (wherein R 1 is an alkyl group having 1 to 4 carbon atoms) is reacted with an acidic aqueous solution. Partial condensate of the partially hydrolyzed product and a titanium alkoxide represented by the following formula (4) Ti (OR 2 ) 4 (4) (where R 2 is an alkyl group having 1 to 4 carbon atoms). Is further subjected to hydrolysis and polycondensation reaction with an acidic aqueous solution to obtain silica titania sol. Highly transparent silica-titania particles having a refractive index of 1.50 or more and less than 1.53 according to claim 1. The method of production.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20339891A JP2956293B2 (en) | 1991-07-19 | 1991-07-19 | Highly transparent silica-titania particles and method for producing the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20339891A JP2956293B2 (en) | 1991-07-19 | 1991-07-19 | Highly transparent silica-titania particles and method for producing the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0524882A true JPH0524882A (en) | 1993-02-02 |
| JP2956293B2 JP2956293B2 (en) | 1999-10-04 |
Family
ID=16473390
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP20339891A Expired - Fee Related JP2956293B2 (en) | 1991-07-19 | 1991-07-19 | Highly transparent silica-titania particles and method for producing the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2956293B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1086362C (en) * | 1999-08-10 | 2002-06-19 | 复旦大学 | Preparation of composite nanometer titania-silica material |
| US6627328B2 (en) | 2000-09-13 | 2003-09-30 | Shin-Etsu Chemical Co., Ltd. | Light-transmissive epoxy resin composition and semiconductor device |
| US6794058B2 (en) | 2000-09-12 | 2004-09-21 | Shin-Etsu Chemical Co., Ltd. | Flip-chip type semiconductor device |
| JP2017036168A (en) * | 2015-08-07 | 2017-02-16 | 株式会社トクヤマ | Silica-titania composite oxide particle and manufacturing method therefor |
-
1991
- 1991-07-19 JP JP20339891A patent/JP2956293B2/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1086362C (en) * | 1999-08-10 | 2002-06-19 | 复旦大学 | Preparation of composite nanometer titania-silica material |
| US6794058B2 (en) | 2000-09-12 | 2004-09-21 | Shin-Etsu Chemical Co., Ltd. | Flip-chip type semiconductor device |
| US6627328B2 (en) | 2000-09-13 | 2003-09-30 | Shin-Etsu Chemical Co., Ltd. | Light-transmissive epoxy resin composition and semiconductor device |
| JP2017036168A (en) * | 2015-08-07 | 2017-02-16 | 株式会社トクヤマ | Silica-titania composite oxide particle and manufacturing method therefor |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2956293B2 (en) | 1999-10-04 |
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