JPS61234A - Production of resin powder - Google Patents

Abstract

PURPOSE:To obtain a fine resin powder easily without need of a grinding step, by spraying a resin solution into a solvent which is a poor solvent for the resin and filtering and drying the formed precipitate. CONSTITUTION:A solution of a resin, preferably one which can be difficultly formed into a fine powder by grinding, such as a polyimide or polyamideimide resin is sprayed into a poor solvent for the resin to precipitate it in the form of a fine powder. The precipitated resin powder is filtered, washed and dried to obtain the purpose fine resin powder. This powder is fine enough to be used as such for molding, but it is molded, if desired, after it is slightly ground for loosening secondary agglomeration.

Description

【発明の詳細な説明】 （産業上の利用分野） 本発明は、微細な樹脂粉末の製造方法に関する１（従来
の技術） 溶液中に溶けている樹脂を固体状Ｃ取り出す手法の一つ
として、その溶液を樹脂の貧溶媒中に′注入し、樹脂を
沈澱凝固させる方法は、特に溶液重合の、後処理工程等
においてよく行われるものである。この場合、以後の洗
浄、乾燥工程における効率の良さや、成形時の流動性の
良さ等の点１．ｓ　＋ら、樹脂固体はできる限り微粉末
状で生成されることが好ましく、このために沈澱槽をホ
モミキサー等の高速攪拌’Ｊ１％　Ｐ￥で攪拌する手法
が通常行われている。Detailed Description of the Invention (Industrial Application Field) The present invention relates to a method for producing fine resin powder (1) (Prior art) As one of the methods for extracting solid C from resin dissolved in a solution, A method in which the solution is injected into a poor solvent for the resin to precipitate and solidify the resin is often carried out particularly in the post-treatment process of solution polymerization. In this case, 1. points such as good efficiency in the subsequent washing and drying steps and good fluidity during molding; It is preferable that the resin solid be produced in the form of a fine powder as much as possible, and for this purpose, a method of stirring the precipitation tank using a homomixer or the like at high speed is usually used.

（発明が解決しようとする問題点） しかしながら、このような方法では得られる沈澱粉末の
細かさには、限度があり、特に粉砕による微粉化が困難
な樹脂においてはこの問題が重要となってくる。(Problem to be solved by the invention) However, there is a limit to the fineness of the precipitated powder that can be obtained by such a method, and this problem becomes particularly important for resins that are difficult to pulverize by pulverization. .

そこで本発明者は、沈澱工程において生成する樹脂粉末
をさらに微粉末化するための手法を鋭意検ｉ・１シた結
果、樹脂溶液を噴霧状にして注入すると効果的であるこ
とを見い出し、本発明に到達した。Therefore, the inventor of the present invention has conducted extensive research on methods for further pulverizing the resin powder produced in the precipitation process, and has discovered that it is effective to inject the resin solution in the form of a spray. invention has been achieved.

（問題点を解決するだめの手段） すなわち、本発明は樹脂を含む溶液を該樹脂に対し貧溶
媒である溶媒中で、該樹脂を凝固させる工程において、
該溶液を噴霧状で該溶媒に接触さゼることを特徴とする
樹脂粉末の製造方法に関するものである。(Another Means to Solve the Problems) That is, the present invention provides a step of coagulating a resin-containing solution in a solvent that is a poor solvent for the resin.
The present invention relates to a method for producing resin powder, characterized in that the solution is brought into contact with the solvent in the form of a spray.

本発明で対象とする樹脂には特に制限がなくどのような
樹脂に対して適用しても従来法にはない効果が発現され
る。づなわち、従来法ではほとんどの場合、沈澱させた
樹脂固体はさらに粉砕され、微粉末化されねばならない
が、本発明の手法によると沈澱した樹脂固体が既に十分
微粉末状となっているため、以後の粉砕工程は省かれる
か又は、大幅に簡略化されるからである。しかし本発明
が特に−大きな効果を現わすのは、次のような樹脂に適
用した場合である。すなわら、 ■　流動性に乏しく、良好な成形品を得るためには、微
粉末であることが必須である樹脂■　粉砕によっては、
微粉末化が困ガな樹脂である。There is no particular restriction on the resin targeted by the present invention, and no matter what kind of resin it is applied to, effects not found in conventional methods will be achieved. In other words, in most cases in the conventional method, the precipitated resin solid must be further crushed and made into a fine powder, but according to the method of the present invention, the precipitated resin solid is already in a sufficiently fine powder form. This is because the subsequent pulverization step is omitted or greatly simplified. However, the present invention exhibits particularly large effects when applied to the following resins. In other words, ■Resin has poor fluidity and must be in fine powder form in order to obtain good molded products.Depending on pulverization,
It is a resin that is difficult to make into a fine powder.

ここで■はいわゆる耐熱性樹脂を示し、■は靭性に富む
樹脂を示しているが、これらの条件を満たずものとして
は、ポリイミド樹脂、ポリアミドイミド樹脂、ポリイミ
ダゾール樹脂、ポリチアゾール樹脂、ポリイミダゾール
樹脂、ポリキノリン、１．　　　　１ｌｌＦａ、＊“１
′１″７″Ｆ’　＃　’）　＞　ｍ　ＩＩＷ・′１１°
°′１等のポリへテロ芳香環樹脂を代表例として挙げる
ことができる。Here, ■ indicates a so-called heat-resistant resin, and ■ indicates a resin with high toughness, but those that do not meet these conditions include polyimide resin, polyamide-imide resin, polyimidazole resin, polythiazole resin, and polyimidazole. Resin, polyquinoline, 1. 1llFa, *“1
'1″7″F'#')> m IIW・'11°
Typical examples include polyhetero aromatic ring resins such as °'1.

これらの樹脂は、成形時の流動性が汎用の樹脂に比べ著
しく劣り、その成形には高温度かつ高圧力を必要どする
が、最も重要な点は、微粉末状でなければならないとい
うことである。微粉末という表現が数値的にどの程度の
粒径を示すかは必ずしも明確でなく、それぞれの樹脂に
よって、異なってくるが、流動性が著しく乏しい場合に
は、粒径が数μｍ程度であることが要求される。そして
この程度の粒径になると、これを粉砕によって達成する
ことは汎用的な粉砕機をもってしては、甚だしく困難に
なるのである。These resins have significantly inferior fluidity when molded compared to general-purpose resins, and require high temperatures and pressures to mold, but the most important point is that they must be in a fine powder form. be. It is not necessarily clear what particle size the expression "fine powder" indicates numerically, and it varies depending on each resin, but in cases where fluidity is extremely poor, the particle size should be around several μm. is required. When the particle size reaches this level, it becomes extremely difficult to achieve this through pulverization using a general-purpose pulverizer.

しかるに、本発明が提供するところの噴霧沈澱法を用い
れば、沈澱直後に樹脂は十分細かくなっており、目的と
する微粉末が容易に得゛られることになる。However, if the spray precipitation method provided by the present invention is used, the resin becomes sufficiently fine immediately after precipitation, and the desired fine powder can be easily obtained.

本発明で噴霧状に沈澱させるために用いる器具は、液体
を噴霧状に放出できるものであれば特にどのような形状
にものでもよいが、塗装に用いられるエアースプレーガ
ンが扱いやすく、便利である。また、沈澱粉末の粒径は
樹脂溶液の濃度により左右され、低温度にするほど細か
い粉末が得られる。しかし、濃度を下げようとすると多
量の溶媒が必要となり、経済的にも好ましくないため、
両者の兼ね合いから適当な濃度が選ばれることになる。The device used for precipitation in the form of a spray in the present invention may be of any shape as long as it can emit liquid in the form of a spray, but an air spray gun used for painting is easy to handle and convenient. . Further, the particle size of the precipitated powder depends on the concentration of the resin solution, and the lower the temperature, the finer the powder can be obtained. However, trying to lower the concentration requires a large amount of solvent, which is not economically desirable.
An appropriate concentration is selected based on the balance between the two.

本発明の手法により得られた粉末は、既に十分細かいた
めそのまま成形に供することもできるが、必要であれば
さらに粉砕を行ってもよい。しかし、この場合の粉砕は
粒子の二次的な凝集を解くことが主な目的であり、粒子
の一次粒径は沈澱された段階で、はぼ決定していると看
做される。すなわち、本発明は、本質的に粉砕工程なし
で微粉末が得られる手法なのである。The powder obtained by the method of the present invention is already sufficiently fine and can be used for molding as it is, but it may be further pulverized if necessary. However, the main purpose of the pulverization in this case is to break up the secondary agglomeration of the particles, and the primary particle size of the particles is considered to be largely determined at the stage of precipitation. That is, the present invention is a method that essentially allows fine powder to be obtained without a pulverization step.

（実施例） 以下に実施例を挙げて、本発明をさらに詳述する。なお
、実施例中の焼結成形試験片は、室温で３Ｘ１０３ｔｔ
ｇｆ／ｃｍ２の圧力をかけて成型した１３　ｍｌｌ１ｘ
　６５　ｍｍｘ　３　ｍｍの圧粉体を、真空中４４０℃
で１時間焼結することにより作製し１＝ものであり、粉
末粒径は走査型電子顕微鏡で観察したものである。又、
使用したエアースプレーガンは、若田塗装機工業（株）
のＷ−６１型であり、粉砕機はホソカ１ノミクロン（株
）のパンタムミルである。(Example) The present invention will be further explained in detail by giving examples below. In addition, the sintered molded test piece in the example was 3X103tt at room temperature.
13ml1x molded under gf/cm2 pressure
A green compact of 65 mm x 3 mm was heated at 440°C in vacuum.
The powder was prepared by sintering for 1 hour at 1=1, and the powder particle size was observed using a scanning electron microscope. or,
The air spray gun used was manufactured by Wakata Painting Equipment Co., Ltd.
W-61 model, and the crusher was a Pantam mill manufactured by Hosoka 1 Micron Co., Ltd.

実施例１ ４．４′−ジアミノジフェニルエーテル（ＤＤＥ）５０
．０６０　（０，２５ｍｏｌ）をＤＭＡｃＩＭに溶解し
、水冷上、良く攪拌しながらピロメリット酸２無水物（
ＰＭＤＡ）５４．５３ｏ　　（０，２５ｍｏｌ）を徐々
に添加した。添加終了後さらに１時間攪拌を続番プだと
ころ、η　ｉｎｈ（ＤＭＡｃ中、淵１皇０．５ｇ／旧、
３０℃で測定）が２．６２の粘稠なポリアミド酸溶液が
得られた。続いてこれにアレトン２１１１を加え、よく
攪拌して均一な溶液とした後、トルエン１０Ｄ、、無水
酢酸０．５Ｑ、ピリジン０．５σを入れた沈澱槽中に攪
拌しながら、エアースプレーガンで噴霧し、粉末状に沈
澱させ／ｊ　ＩＩこれを濾過した後、アセトンで３回洗
浄を繰り返し、真空中２００℃で１０時間乾燥させた。Example 1 4.4'-diaminodiphenyl ether (DDE) 50
．． 060 (0.25 mol) was dissolved in DMAcIM, and pyromellitic dianhydride (
PMDA) 54.53o (0.25 mol) was gradually added. After the addition was completed, stirring was continued for an additional hour.
A viscous polyamic acid solution with a temperature (measured at 30° C.) of 2.62 was obtained. Next, Aletone 2111 was added to this, stirred well to make a homogeneous solution, and then sprayed with an air spray gun while stirring into a precipitation tank containing 10D of toluene, 0.5Q of acetic anhydride, and 0.5σ of pyridine. This was precipitated into a powder, which was filtered, washed three times with acetone, and dried in vacuo at 200° C. for 10 hours.

得られたポリイミド粉末を粉砕した後、焼結成形し曲げ
試験を行ったところ、曲げ強度９．７ｋｏｆ／ｍｍ２で
あった。なお、この時粉末粒径は３μｍ〜１０μｍであ
った。また粉砕けずにそのまま成形したものでも、曲げ
強度９　、　Ｏｋｇｆ　／　ｍｍ’２ぐあり、十分実用
に供せるレベルであった。The resulting polyimide powder was pulverized, sintered, and subjected to a bending test, and the bending strength was 9.7 kof/mm2. Note that the powder particle size at this time was 3 μm to 10 μm. Moreover, even when it was molded as it was without being crushed, the bending strength was 9.0 kgf/mm'2, which was at a level that could be used for practical purposes.

実施例２ ＤＤＥ５０．０６（１（０，２５ｍｏりをｌ）　Ｍ　Ａ
ｃＮ１に溶解し、水冷下、ベンゾフェノンテトラカルボ
ン酸２無水物（Ｂ　Ｔ’　ＤΔ）８０．５６（］（０，
２５ｍｏｌ）を徐々に加え、ｒ）　　ｉｎｈ（ＤＭＡＣ
中、濃度０．５（１／旧、３０℃で測定）が１゜９８の
ポリアミド酸溶液を得た。このものを７セトン２ｎで希
釈した後、１アースプレーガンを用いて沈澱させた。引
き続き、実施例１と同様に洗浄、乾燥、粉砕した後、焼
結成形したところ、試験片の曲げ強度は１０　、５　ｋ
Ｏｆ　／ｍｍ２であった。Example 2 DDE50.06 (1 (0.25mol)) M A
Benzophenonetetracarboxylic dianhydride (B T' DΔ)80.56(](0,
25 mol) was gradually added, r) inh (DMAC
A polyamic acid solution with a concentration of 0.5 (1/old, measured at 30°C) of 1°98 was obtained. This material was diluted with 2N of 7setone and then precipitated using a 1Earth spray gun. Subsequently, the test piece was washed, dried, crushed and sintered in the same manner as in Example 1, and the bending strength of the test piece was 10.5K.
Of/mm2.

比較例１ 実施例１において、エアースプレーガンを用い（ずに、
ピペットで徐々に添加し、沈澱させた。ま＋ま た、このとき沈澱槽は激しく攪拌しておいた。しかしな
がら、沈澱物は塊状となり、粉砕を２回繰り返したにも
かがねらず、得られた粉末は粒径的８０μｍと粗いもの
であった。このものから焼結成形して得た試験片の曲げ
強度は３．０ｋｏｆ　／ｍｍ２と非常に低く、もろいも
のであった。Comparative Example 1 In Example 1, an air spray gun was used (without
Add slowly with a pipette to allow precipitation. Also, at this time, the sedimentation tank was vigorously stirred. However, the precipitate became agglomerated, and even after repeated pulverization twice, the obtained powder had a coarse particle size of 80 μm. The bending strength of a test piece obtained by sintering and forming this material was very low at 3.0 kof/mm2, and it was brittle.

比較例２ 実施例２にａ３いて、エアースプレーガンを用いずに沈
澱させたところ、沈澱物は塊状となった。Comparative Example 2 When a3 was used in Example 2 to precipitate without using an air spray gun, the precipitate became lumpy.

これを粉砕後、焼結成形したが曲げ強度４．２ｋ（１ｆ
／ｍｍ２と非常に低かった。After crushing this, it was sintered and formed, but the bending strength was 4.2k (1f
/mm2, which was very low.

（弁明の効果） 本発明によれば、沈澱した樹脂固体が既に十分微粉末状
どなっているため、以後の粉砕工程は省かれるか又は、
大幅に簡略化される。また、従来の粉砕法によっては、
微粉末化が困難な樹脂などに有効である。(Effect of explanation) According to the present invention, since the precipitated resin solid is already in a sufficiently fine powder state, the subsequent pulverization step can be omitted or
greatly simplified. Also, depending on the conventional pulverization method,
Effective for resins that are difficult to make into fine powder.

特に、ポリイミド樹脂は代表的な耐熱樹脂であるが、溶
融流動性が非常に乏しいため良好な成形品を得るために
は、粉末の粒径は数μｍ程度でなければならない。この
ような微粉末を粉砕により得ることは非常に困難なので
あるが、本発明によれば、これを容易に得ることができ
る１、かくして本発明は、樹脂微粉末の製造方法として
極めて有効な手法となるのである。In particular, polyimide resin is a typical heat-resistant resin, but it has very poor melt flowability, so in order to obtain a good molded product, the particle size of the powder must be on the order of several μm. It is very difficult to obtain such a fine powder by pulverization, but according to the present invention, it can be easily obtained1.Thus, the present invention is an extremely effective method for producing fine resin powder. It becomes.

Claims (1)

【特許請求の範囲】[Claims] （１）樹脂を含む溶液を該樹脂に対し貧溶媒である溶媒
中で、該樹脂を凝固させる工程において、該溶液を噴霧
状で該溶媒に接触させることを特徴とする樹脂粉末の製
造方法。(1) A method for producing a resin powder, which comprises, in the step of coagulating a solution containing a resin in a solvent that is a poor solvent for the resin, bringing the solution into contact with the solvent in the form of a spray.