Abstract: The toner contains binder resin-containing toner particles and silica fine particle S1, wherein the weight-average particle diameter of the toner is 4.0-15.0 ?m, both inclusive, peaks originating with the silica fine particle S1 are observed in 29 Si-NMR measurement of the silica fine particle S1, and, in the spectrum obtained by 29Si CP/MAS NMR or 29Si DD/MAS NMR, the peak area of a peak corresponding to the D1 unit structure in the silica fine particle S1, the peak area of a peak corresponding to the D2 unit structure in the silica fine particle S1, and the peak area of a peak corresponding to the Q unit structure in the silica fine particle S1 satisfy a prescribed relationship.

Abstract: A single-segment filter having a filter plug uses a high-rigidity and high-permeability paper longitudinal rigidity of which is 30 or higher as measured in accordance with JIS P8143 and air permeability of which is 1000 CORESTA units or greater as a filter plug wrapper wrapping a filter material, and a multisegment filter having a plurality of filter plugs uses the high-rigidity and high-permeability paper as a filter plug wrapper wrapping a filter material and/or a shaping paper joining plurality of filter plugs. A cigarette comprises the particular filter.

Abstract: A water-dispersible sheet and a cigarette using the sheet are disclosed. The sheet comprises a water-resolvable base paper made from fibrous raw materials and a water-dispersible coating layer containing water-soluble polymer and an alkaline compound. The sheet is also produced through an impregnation treatment for a water-resolvable base paper with a coating mixture containing water-soluble polymer and an alkaline compound, wherein said water-resolvable base paper is made from a mixture of water-dispersible fibers and fibrous carboxymethyl cellulose acid or fibrous carboxyethyl cellulose acid. The gas-permeability of the water-dispersible sheet is controlled by the water-dispersible coating layer or the impregnation treatment.

Abstract: A water-dispersible sheet for cigarettes and a cigarette using the sheet are described. The sheet comprises a water-resolvable base paper and a water-dispersible coating layer containing water-soluble polymer formed on the surface of the base paper, whereby the sheet is adjusted to have an air-permeability of not more than 200 coresta measured with a paper permeability meter, or to have an air-resistance within the range of 0 to 50000 second/100 ml measured with an Oken type air-resistance tester. The water-resolvable base paper is made from fibrous raw materials containing not less than 20% by weight of water-dispersible fibers having fiber dimensions of a l/D value of 0.45 or lower and a L/D value of 60 or lower and a water-retention value of 95% or lower. The sheet is suitable for use as filter joining paper or filter plug wrap for cigarettes.