| 摘要 |
<p>PROBLEM TO BE SOLVED: To prepare the subject composition able to form toner excellent in durability which can give photographic images having high resolution and not causing fogging and improper fixing, by applying specific polyolefin particles and a vinyl-based copolymer having a specific BET specific surface area. SOLUTION: This composition is composed of (A) 0.1-12 pts.wt. of polyolefin particle having a mean volume particle diameter of 0.5-8μm, a weight-average molecular weight (Mw ) o 3×10<3> -1.5×10<4> , a melting point of 100-130'C and a specific gravity of <1.0 and (B) 100 pts.wt. of vinyl-based copolymer containing a styrene-based monomer and a (meth)acrylate monomer as structural units. The composition has in its M. distribution one maximum value (PL) in lower Mw region from 3×10<3> to 4×10<4> an one maximum value (PH) in higher Mw region from 3×10<5> to 8×10<6> , where PH/PL is 0.15-1.0, and has a molecular weight distribution of 10-180, a glass transition temperature of >=50 deg.C, a specific gravity (or a density) in a packed state of <0.68 g/cc, an angle of repose of <27 deg. and a BET specific surface area of 0.02-0.2 m<2> /g.</p> |
