porous resin particles are made of a polymer of a monomer mixture . Here, the monomer mixture, (meth) having an ethylenically unsaturated group only in the acrylic acid residue, mono (meth containing at least one hydroxyl group and an ether group and an ester group in the alcohol residue and a) acrylic acid ester monomer 3-40% by weight, with other monofunctional vinyl-based monomer 10 to 69% by weight having an ethylenically unsaturated group 1, two or more ethylenically unsaturated groups and a multi-functional vinyl monomers 30 to 70% by weight. .BACKGROUND 1多孔質樹脂粒子は、単量体混合物の重合体からなるものである。ここで、前記単量体混合物は、(メタ)アクリル酸残基中にのみエチレン性不飽和基を有し、エーテル基およびエステル基の少なくとも一方と水酸基とをアルコール残基中に含むモノ(メタ)アクリル酸エステル系単量体3~40重量%と、エチレン性不飽和基を1個有する他の単官能ビニル系単量体10~69重量%と、エチレン性不飽和基を2個以上有する多官能ビニル系単量体30~70重量%とを含む。【選択図】図1
