POLYMER FINE PARTICLE FOR GRINDING MEDIA

PROBLEM TO BE SOLVED: To provide a polymer fine particle for grinding media in which, when used as a grinding medium such as a grinding mill, an efficient grinding is carried out because of narrow particle size distribution and perfectly spherical shape, as well as deformation due to heat generation during grinding is less.SOLUTION: By using a polymer fine particle for grinding media comprising a polymer having a glass transition temperature of 160°C or more and 400°C or less and having an average particle size of 50 μm or more and 1000 μm or less, a particle size distribution index of 1 to 3 and a sphericity of 80 or more, deformation due to heat generation during grinding is less and an efficient grinding is carried out as well as contamination to ground material is less likely to occur.SELECTED DRAWING: None 【課題】粉砕ミルなどの粉砕媒体として用いる際に、粒子径分布が狭く、真球状であるため効率的な粉砕が行われ、かつ粉砕時の発熱による変形が少ない粉砕媒体用ポリマー微粒子を提供する。【解決手段】ガラス転移点が１６０℃以上４００℃以下のポリマーから成り、平均粒子径が５０μｍ以上、１０００μｍ以下であり、かつ粒子径分布指数が１〜３であり、真球度が８０以上である粉砕媒体用ポリマー微粒子を用いることで、粉砕時の発熱による変形が少なく効率的な粉砕が行われ、かつ粉砕物へのコンタミネーションが起きにくい。【選択図】なし