Abstract
Low-density paper is now most trendy in Japanese market in recent years. Consumption of low-density paper, called “bulky paper”, becomes higher and the market grows getting larger. Many types of “bulky paper” have been developed, and most of them are used for high quality printing paper, million-seller book, wood-free printing paper, and so on.
One of the most important feature of “bulky paper” is a thickness of the paper. Although the basis weight of paper is same, bulky paper is thicker, lighter and softer than traditional ones. Paper strength of bulky paper is supposed to be weaker, therefore, it is important to prevent decreasing tensile strength or internal bond strength of the paper. In order to produce well-balanced sheet, addition level of paper strength agent, such as cationic starch, modified polyacrylamide, and bulking promoters (agent) , organic and inorganic compounds, are discussed.
