Abstract: The present invention relates to a masking tape base material using a machine-made Japanese paper as a base paper. The machine-made Japanese paper comprises a mercerized softwood pulp and a kraft pulp. The weight percent of the mercerized softwood pulp in a mixture of the mercerized softwood pulp and the kraft pulp is from 10 to 70% by weight. The machine-made Japanese paper is impregnated with a resin having a glass transition temperature of not higher than ?25° C. in an amount of 20% by weight or more. One surface of the impregnated machine-made Japanese paper is further coated with a resin having a glass transition temperature (Tg) of from 0 to 40° C. in a dry coating amount of from 2 to 20 g/m2.

Abstract: The present invention relates to an impregnation-coating type Japanese paper masking tape base material obtained by coating a resin having a glass transition temperature (Tg) of from 0 to 40° C. in a dry coating amount of from 2 to 20 g/m2 on one surface of a paper in which a machine-made Japanese paper having a basis weight of from 25 to 40 g/m2, in which a fiber component thereof includes a mercerized softwood pulp and a kraft pulp, and a blending ratio of the mercerized softwood pulp is from 10 to 70% by weight, is impregnated with a resin having a glass transition temperature of not higher than ?25° C. in an amount of 20% by weight or more.