Low-substituted hydroxypropylcellulose powder

摘要

Provided is a low-substituted hydroxypropylcellulose powder having high compressibility, good flowability and excellent disintegration. The powder has an average particle size of 10 to 100 μm and a specific surface area measured by BET method of at least 1.0 m2/g.

主权项

1. A low-substituted hydroxypropylcellulose powder having:
a molar substitution number per anhydrous glucose unit of 0.05 to 1.0; an average particle size of 10 to 100 μm; a specific surface area measured by the BET method of at least 1.0 m2/g; an elastic recovery ratio of not greater than 7% when compressed at a compression pressure of 50 MPa; and a repose angle of not greater than 42°, wherein the elastic recovery ratio of the powder is calculated according to the following equation:Elastic⁢⁢recovery⁢⁢ratio=(tablet⁢⁢thickness⁢⁢after⁢⁢30⁢⁢seconds-minimum⁢⁢tablet⁢⁢thickness)(minimum⁢⁢⁢tablet⁢⁢thickness)×100  wherein tablet thickness is determined for a tablet obtained by compression of the powder into a tablet with a weight of 480 mg and a compression force of 50 MPa using a flat shape with a flat contact face for a tablet diameter of 11.3 mm, wherein minimum tablet thickness is determined at its lowest point when the powder is compressed by an upper punch of a flat shape unit with a fixed lower punch, and tablet thickness after 30 seconds is the tablet thickness determined 30 seconds after the upper punch is removed.