JPH0628718B2 - Method for producing synthetic resin-coated glass particles - Google Patents
Method for producing synthetic resin-coated glass particlesInfo
- Publication number
- JPH0628718B2 JPH0628718B2 JP63110907A JP11090788A JPH0628718B2 JP H0628718 B2 JPH0628718 B2 JP H0628718B2 JP 63110907 A JP63110907 A JP 63110907A JP 11090788 A JP11090788 A JP 11090788A JP H0628718 B2 JPH0628718 B2 JP H0628718B2
- Authority
- JP
- Japan
- Prior art keywords
- particles
- monomer
- glass particles
- coated
- glass
- 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
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C17/00—Surface treatment of glass, not in the form of fibres or filaments, by coating
- C03C17/28—Surface treatment of glass, not in the form of fibres or filaments, by coating with organic material
- C03C17/32—Surface treatment of glass, not in the form of fibres or filaments, by coating with organic material with synthetic or natural resins
- C03C17/328—Polyolefins
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Glanulating (AREA)
- Surface Treatment Of Glass (AREA)
- Polymerisation Methods In General (AREA)
- Liquid Crystal (AREA)
Description
【発明の詳細な説明】 （イ）産業上の利用分野 この発明は合成樹脂被覆ガラス粒子の製造方法に関す
る。さらに詳しくは液晶表示素子等のスペーサとして使
用される粒子の製造方法に関する。TECHNICAL FIELD The present invention relates to a method for producing synthetic resin-coated glass particles. More specifically, it relates to a method for producing particles used as spacers for liquid crystal display devices and the like.
（ロ）従来の技術 液晶表示素子等のスペーサとして使用される物は、ごく
微小の間隙を正確に保持できるものでなければならず、
これは微粒子状の無機球体および有機球体が用いられ
る。しかし前者は圧縮時母材にキズがつく等の欠点を有
し、一方後者は圧縮後反発力があり寸法の誤差が大きく
なるという欠点を有している。従ってこれらの欠点を解
消するものとして表面に合成樹脂等の有機物を被覆した
無機球体を用いることが考えられる。ここで、微粒子状
の無機球体を合成樹脂で被覆する方法として、表面融合
法（以下メカノフュージョンという）が知られている。
これはガラス球等の無機微粒子と所定の超微細樹脂粉体
とを混合し、強い機械的エネルギを加えることにより、
粒子同志に激しい摩擦を起こして発熱させ、この発熱に
より無機粒子表面に付着した樹脂粉体を軟化させて膜化
させる方法である。(B) Conventional technology Materials used as spacers for liquid crystal display elements, etc. must be capable of accurately maintaining very small gaps,
For this, fine-particle inorganic spheres and organic spheres are used. However, the former has a defect that the base material is scratched during compression, while the latter has a defect that there is a repulsive force after compression and a dimensional error becomes large. Therefore, as a solution to these drawbacks, it is conceivable to use an inorganic sphere whose surface is coated with an organic substance such as a synthetic resin. Here, a surface fusion method (hereinafter referred to as mechanofusion) is known as a method of coating the inorganic fine particles in a synthetic resin.
This is by mixing inorganic fine particles such as glass spheres with a predetermined ultrafine resin powder and applying strong mechanical energy,
This is a method of causing intense friction between particles to generate heat, and the heat generation softens the resin powder adhered to the surface of the inorganic particles to form a film.
（ハ）発明が解決しようとする課題 しかしながら、上記メカノフュージョンで得られたもの
は、微小的に観察すれば被膜表面の平滑化さに欠けるも
のであり、また無機粒子の表面全体が均一にしかも完全
に被膜化されていないため、衝撃等により割れ起こし無
機粒子からの剥離が生じやすい。(C) Problems to be Solved by the Invention However, what is obtained by the above-mentioned mechanofusion is lacking in smoothness of the coating surface when observed microscopically, and the entire surface of the inorganic particles is uniform. Since it is not completely formed into a film, it tends to crack due to impact or the like and peel off from the inorganic particles.
この発明はかかる状況に鑑みなされたものであり、均一
化された表面被覆樹脂層を有するガラス粒子の製造方法
を提供しようとするものである。The present invention has been made in view of such circumstances, and an object of the present invention is to provide a method for producing glass particles having a uniform surface-coating resin layer.
（ニ）課題を解決するための手段 かくしてこの発明によれば、表面融合法によりポリマ層
が不均一に被覆されたガラス粒子を、該ポリマに相溶性
のビニル系モノマが懸濁または乳化された水系媒体中に
分散させ、このガラス粒子を攪拌させた状態下で上記ビ
ニル系モノマの重合条件に付すことにより、平滑化され
た表面被覆層を有するガラス粒子を得ることを特徴とす
る合成樹脂被覆ガラス粒子の製造方法が提供される。(D) Means for Solving the Problems Thus, according to the present invention, the glass particles in which the polymer layer is nonuniformly coated by the surface fusion method are prepared by suspending or emulsifying a vinyl monomer compatible with the polymer. Dispersing in an aqueous medium, and subjecting the glass particles to a polymerization condition of the vinyl-based monomer under a state of stirring to obtain glass particles having a smoothed surface coating layer, synthetic resin coating A method of manufacturing glass particles is provided.
この発明の方法の対象となる無機粒子は、例えば液晶等
のスペーサとして用いることができる程度の微細な球状
粒子が最も適しており、その大きさとしては平均粒径５
〜25μｍのものが適している。またこのガラス粒子の材
質としては上記の用途に耐え得る硬度または強度を有す
るものが選択される。The fine inorganic particles to be used in the method of the present invention are, for example, fine spherical particles that can be used as spacers for liquid crystals and the like, and the average particle size is 5
The one of up to 25 μm is suitable. Further, as the material of the glass particles, one having hardness or strength capable of withstanding the above-mentioned use is selected.
この発明においては、上記ガラス粒子の表面が予めポリ
マ層で不均一に被覆されたものが用いられる。これは上
記粒径を有するガラス粒子を対象として施される公知の
いずれの被覆方法によっても得られる被覆粒子を意味す
るが、そのうち被覆の不均一化の度合が最も小さくなさ
れる被覆方法により被覆処理された被覆粒子が好まし
い。この好ましい被覆処理としては例えば、メカノフュ
ージョン（前掲）とぼれる表面融合法を挙げることがで
きる。上記被覆されるポリマ層は、上記のごとく選択さ
れるガラス粒子の材質に対応して、これと接着性の高い
ものが選択される。例えば、アクリル系樹脂が好ましい
ものとして挙げられる。なお、上記ポリマ被覆層の形成
の際には適当な結合助剤、例えばシランカップリング材
のごときもの、を用いてもよい。In the present invention, the above-mentioned glass particles whose surfaces are nonuniformly coated with a polymer layer in advance are used. This means coated particles obtained by any known coating method applied to glass particles having the above-mentioned particle diameter, of which the coating treatment by the coating method by which the degree of nonuniformity of the coating is minimized. Coated particles are preferred. This preferred coating treatment includes, for example, the surface fusion method which is blunt with mechanofusion (supra). The polymer layer to be coated is selected from those having high adhesiveness with the material of the glass particles selected as described above. For example, acrylic resins are preferred. In addition, when forming the polymer coating layer, a suitable bonding aid, such as a silane coupling agent, may be used.
この発明において、上記のごときポリマ層で不均一に表
面被覆されたガラス粒子（以下不均一被覆粒子という）
は、所定のモノマが懸濁または乳化された水系媒体中に
分散保持される。上記所定のモノマは、前記ポリマ層と
相溶性のビニル系モノマでかつそのポリマ相を柔軟にし
うるものが選択される。上記ポリマを柔軟にしうると
は、そのポリマ相の粘度を、上記水系媒体中での押圧力
や粒子自身の回転等により発生する力等により変形可能
な程度に低下させうることを意味する。上記モノマして
は、通常ポリマ相を形成するポリマのモノマが好ましい
が、これに限定されない。上記水系媒体は、懸濁安定性
を高めるために公知の懸濁安定剤が添加されて調製され
る。該水系媒体はエマルジョンに調製されることが好ま
しい。上記水系媒体を調製する際、上記モノマは用いる
不均一被覆粒子の10〜40重量％程度で用いられることが
好ましい。In the present invention, glass particles whose surface is nonuniformly coated with a polymer layer as described above (hereinafter referred to as nonuniformly coated particles)
Are dispersed and held in an aqueous medium in which a predetermined monomer is suspended or emulsified. The predetermined monomer is selected as a vinyl-based monomer compatible with the polymer layer and capable of softening the polymer phase. The phrase "the polymer can be made flexible" means that the viscosity of the polymer phase can be lowered to such an extent that it can be deformed by a pressing force in the aqueous medium, a force generated by rotation of the particles themselves, or the like. As the above-mentioned monomer, a monomer of a polymer which usually forms a polymer phase is preferable, but not limited thereto. The above aqueous medium is prepared by adding a known suspension stabilizer in order to enhance suspension stability. The aqueous medium is preferably prepared as an emulsion. When preparing the aqueous medium, the monomer is preferably used in an amount of about 10 to 40% by weight of the non-uniformly coated particles used.
この発明において、前記不均一被覆粒子は、上記のごと
く調製される水系媒体中に分散保持される。この分散保
持は攪拌により達成される。該分散保持は、モノマの上
記不均一被覆粒子のポリマ層への接触・含浸およびポリ
マ層中もしくは層上で該モノマの重合が達成されうる条
件下で行われる。該条件としては、例えば、前者の接触
・含浸過程および後者の重合過程共、通常嫌気雰囲気下
で、前者は温度10〜60℃で0.5〜２時間、後者は温度70
〜90℃で３〜５時間攪拌維持する等が挙げられる。In this invention, the nonuniformly coated particles are dispersed and held in the aqueous medium prepared as described above. This dispersion retention is achieved by stirring. The holding of the dispersion is carried out under conditions such that contact and impregnation of the heterogeneous coated particles of the monomer with the polymer layer and polymerization of the monomer in or on the polymer layer can be achieved. The conditions include, for example, the former contact / impregnation process and the latter polymerization process, usually in an anaerobic atmosphere, the former at a temperature of 10 to 60 ° C. for 0.5 to 2 hours, and the latter at a temperature of 70.
Examples of the method include maintaining stirring at ˜90 ° C. for 3 to 5 hours.
上記のごとき分散保持により、前記不均一被覆粒子の表
面被覆の均一化および平滑化が達成される。By maintaining the dispersion as described above, uniformization and smoothing of the surface coating of the nonuniform coating particles are achieved.
（ホ）作用 この発明によれば、表面が不均一なポリマ層で被覆され
たガラス粒子を、該ポリマに相溶性のビニル系モノマが
懸濁または乳化された水系媒体中に分散保持することに
より、前記ポリマ層に上記モノマが接触・含浸され、こ
のポリマ層が柔軟化されると共に、このポリマ層上もし
くは層内で上記モノマの重合が進行され、また水系媒体
中の界面張力および分散に伴うガラス粒子の運動によ
り、該ガラス粒子の表面被覆層が平滑化されることとな
る。(E) Action According to the present invention, glass particles coated with a polymer layer having an uneven surface are dispersed and held in an aqueous medium in which a vinyl monomer compatible with the polymer is suspended or emulsified. The polymer layer is contacted and impregnated with the monomer to soften the polymer layer, polymerization of the monomer proceeds on or in the polymer layer, and the interfacial tension and dispersion in an aqueous medium accompany the polymerization. The movement of the glass particles results in smoothing the surface coating layer of the glass particles.
以下実施例によりこの発明を詳細に説明するが、これに
よりこの発明は限定されるものではない。Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited thereto.
（ヘ）実施例 実施例１ まず、ポリビニルアルコール（ＰＶＡ）６ｇ、ラウリル
硫酸ナトリウム0.12ｇ、エチレンジアミンテトラ酢酸の
２ナトリウム塩 1.2ｇを 600mlの水に溶解し分散媒を調
製する。次に過酸化ベンゾイル0.03ｇメチルメタクリレ
ート（ＭＭＡ）モノマ14ｇ、γ−メタクリロキシプロピ
ルトリメトキシシラン１ｇを充分混合・溶解した後、上
記分散媒全量を加え、高速攪拌下（特殊機化加工業製ホ
モミキサを使用）で乳化させ、モノマエマルジョンを調
製した。(F) Example 1 First, 6 g of polyvinyl alcohol (PVA), 0.12 g of sodium lauryl sulfate, and 1.2 g of a disodium salt of ethylenediaminetetraacetic acid are dissolved in 600 ml of water to prepare a dispersion medium. Next, 0.03 g of benzoyl peroxide, 14 g of methyl methacrylate (MMA) monomer, and 1 g of γ-methacryloxypropyltrimethoxysilane were thoroughly mixed and dissolved, and then the entire amount of the above-mentioned dispersion medium was added, and the mixture was stirred under high speed (a homomixer manufactured by Special Machinery Industry). Was used) to prepare a monomer emulsion.
一方１オートクレーブに上記モノマエマルジョンおよ
びポリメチルメタクリエート（ＰＭＭＡ）被覆ガラスビ
ーズ（平均粒径８μ） 100ｇを仕込み、Ｎ２置換後、常
温攪拌下で充分分散させた後、２時間保持して上記ガラ
スビーズの被覆ＰＭＭＡポリマ層にＭＭＡモノマ充分吸
収含浸させる。２時間経過後、約１時間かけて75℃に昇
温し３時間保持した後、90℃に昇温して２時間保持して
重合を完結させた後、常温まで冷却して取り出した。得
られた分散粒子は静置後上澄み液を捨て、新たに水を加
える操作を繰り返すことで洗浄した後ロ別し、乾燥し
た。On the other hand, 100 g of the above-mentioned monomer emulsion and polymethylmethacrylate (PMMA) -coated glass beads (average particle size: 8 μ) were charged in one autoclave, and after N 2 substitution, sufficiently disperse under normal temperature stirring and then hold for 2 hours to hold the above glass. The coated PMMA polymer layer of beads is fully impregnated with MMA monomer. After 2 hours, the temperature was raised to 75 ° C. over about 1 hour and kept for 3 hours, then raised to 90 ° C. and kept for 2 hours to complete the polymerization, then cooled to room temperature and taken out. The obtained dispersed particles were allowed to stand, then the supernatant liquid was discarded, and the procedure of adding new water was repeated to wash the separated particles, which were then separated by filtration and dried.
得られた被覆粒子は、ガラスビーズに厚さ１μｍの均一
なＰＭＭＡ被覆層を有しており、電子顕微鏡写真で見る
と表面状態は平滑であった。The obtained coated particles had a uniform PMMA coating layer with a thickness of 1 μm on glass beads, and the surface condition was smooth when viewed by an electron micrograph.
実施例２ ＭＭＡモノマ14の代わりに、ＭＭＡモノマ13ｇ、トリメ
チロールプロパントリメタクリエート１ｇを使用する他
は、実施例１と同様に重合した。Example 2 Polymerization was conducted in the same manner as in Example 1 except that 13 g of MMA monomer and 1 g of trimethylolpropane trimethacrylate were used instead of MMA monomer 14.
得られた被覆粒子は、ガラスビーズ厚さ１μｍの均一な
ＰＭＭＡ被覆層を有しており、電子顕微鏡写真で見ると
表面状態は平滑であった。The obtained coated particles had a uniform PMMA coating layer having a glass bead thickness of 1 μm, and the surface condition was smooth when viewed by an electron micrograph.
実施例３ ＭＭＡモノマ14ｇの代わりに、ＭＭＡモノマ12ｇ、ブチ
メタクリレート（ＢＭＡ）モノマ２ｇを使用する他は実
施例１と同様に重合した。Example 3 Polymerization was performed in the same manner as in Example 1 except that 12 g of MMA monomer and 2 g of butymethacrylate (BMA) monomer were used instead of 14 g of MMA monomer.
得られた被覆粒子は、ガラスビーズに厚さ１μｍの均一
なＰＭＭＡ被覆層を有しており、電子顕微鏡写真で見る
と表面状態は平滑であった。The obtained coated particles had a uniform PMMA coating layer with a thickness of 1 μm on glass beads, and the surface condition was smooth when viewed by an electron micrograph.
実施例４ 実施例１と同様に分散媒を調製し、次に過酸化ベンゾイ
ル0.1ｇ、ＭＭＡモノマ40ｇ、γ−メタクリロキシプロ
ピルトリメトキシシラン10ｇを充分に混合・溶解した
後、上記分散媒 200mlを使用してモノエマルジョンを調
製する。１オートクレーブに残りの分散媒および実施
例１で用いたものと同様のＰＭＭＡ被覆ガラスビーズ 1
00ｇを仕込み、Ｎ２置換後常温攪拌下で充分分散させ、
その後70℃に昇温した。70℃でモノマエマルジョンの1
／5量を投入し、この後１時間毎にそれぞれ1／5量ずつ
分割投入し、最終投入御５時間を経過してから90℃に昇
温し、２時間保持して重合を完結させた後、常温まで冷
却して取り出した。Example 4 A dispersion medium was prepared in the same manner as in Example 1, and then 0.1 g of benzoyl peroxide, 40 g of MMA monomer and 10 g of γ-methacryloxypropyltrimethoxysilane were sufficiently mixed and dissolved, and then 200 ml of the above dispersion medium was added. Use to prepare a monoemulsion. 1 remaining autoclave dispersion medium and PMMA coated glass beads similar to those used in Example 1 1
Charge 00 g, replace with N 2 and thoroughly disperse under normal temperature stirring,
Then, the temperature was raised to 70 ° C. 1 of Monomer Emulsion at 70 ℃
/ 5 amount was charged, and thereafter, 1/5 amount was dividedly charged every 1 hour, and after 5 hours from the final charging, the temperature was raised to 90 ° C. and maintained for 2 hours to complete the polymerization. Then, it was cooled to room temperature and taken out.
得られた被覆粒子は、ガラスビーズ厚さ１μｍの均一な
ＰＭＭＡ被覆層を有しており、電子顕微鏡写真で見ると
表面状態は平滑であった。The obtained coated particles had a uniform PMMA coating layer having a glass bead thickness of 1 μm, and the surface condition was smooth when viewed by an electron micrograph.
（ト）発明の効果 この発明によれば、樹脂で均一に表面被覆されかつ表面
が平滑化された微細ガラス粒子を得ることができる。ま
た液晶等のスペーサとして好適なものを提供することが
できる。(G) Effect of the Invention According to the present invention, it is possible to obtain fine glass particles whose surface is uniformly coated with a resin and whose surface is smoothed. Further, a suitable spacer for liquid crystal or the like can be provided.
───────────────────────────────────────────────────── 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 // Ｇ０２Ｆ 1/1339 ５００ 8302−2Ｋ ─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. 5 Identification code Office reference number FI technical display location // G02F 1/1339 500 8302-2K
Claims (1)
されたガラス粒子を、該ポリマに相溶性のビニル系モノ
マが懸濁または乳化された水系媒体中に分散させ、この
ガラス粒子を攪拌分散させた状態下で上記ビニル系モノ
マの重合条件に付すことにより、平滑化された表面被覆
層を有するガラス粒子を得ることを特徴とする合成樹脂
被覆ガラス粒子の製造方法。1. A glass particle having a polymer layer unevenly coated by a surface fusion method is dispersed in an aqueous medium in which a vinyl monomer compatible with the polymer is suspended or emulsified, and the glass particle is stirred. A method for producing synthetic resin-coated glass particles, which comprises subjecting the vinyl-based monomer to a polymerization condition in a dispersed state to obtain glass particles having a smoothed surface coating layer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63110907A JPH0628718B2 (en) | 1988-05-06 | 1988-05-06 | Method for producing synthetic resin-coated glass particles |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63110907A JPH0628718B2 (en) | 1988-05-06 | 1988-05-06 | Method for producing synthetic resin-coated glass particles |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01282139A JPH01282139A (en) | 1989-11-14 |
| JPH0628718B2 true JPH0628718B2 (en) | 1994-04-20 |
Family
ID=14547680
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63110907A Expired - Lifetime JPH0628718B2 (en) | 1988-05-06 | 1988-05-06 | Method for producing synthetic resin-coated glass particles |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0628718B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2020241665A1 (en) * | 2019-05-31 | 2020-12-03 | 国立大学法人京都大学 | Macrophage imaging agent |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6296539A (en) * | 1985-10-23 | 1987-05-06 | Tokuyama Soda Co Ltd | Composite polymer particles and their manufacturing method |
| JPH0735406B2 (en) * | 1986-06-24 | 1995-04-19 | 株式会社トクヤマ | Method for producing composite polymer particles |
-
1988
- 1988-05-06 JP JP63110907A patent/JPH0628718B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01282139A (en) | 1989-11-14 |
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